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Prr i m a r y 1 P Textbook
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The 5E Model – Guided Inquiry
Re ga le du ca tio n
The Let’s Do Science series is based on the Biological Sciences Curriculu Curriculum riculu Study (BSCS) 5E teaching and learning instructional model. The he 5E E model is centered on the idea that students understand science concepts oncepts pts best by using prior knowledge to pose questions and find answers rs through hrough guided inquiry. This hands-on approach, integrated with engineering ng g and design skills, sk s has students learn science by doing science. Teachers chers guide the llearning process and are able to assess student performance evaluating student mance ce by evalua explanations and the application of newly acquired quired d knowledge knowledg knowled and skills.
Engage
The Engage phase of the 5E model provides videss students with w the opportunity to demonstrate their prior knowledge and understanding of the topic or understand concept. Students are presented with which serves to h an n activity or question q motivate and engage students as they hey begin the llesson. Teachers identify and correct any misconceptions and d gather data dat from students which will guide informed teaching and learning. earning. ng Essential to stimulating and students is the use of mixed media d engaging gaging stude st such as colorful photos, illustrations found throughout the trations tions and diagrams d textbooks and activity books. Let’s Science also includes extensive bo boo t’s Do S digital resources such videos, interactive lessons, virtual labs, h as narrated narra nar id slideshows and more. re.
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Explore
Re ga le du ca tio n
This phase encourages exploration of concepts and skills through gh handshan on activities and investigations. Students are encouraged to work togethe together red learning earn and apply various process skills while gaining concrete, shared ch students experiences. These experiences provide a foundation for which epts.. This studentstuden can refer to while building their knowledge of new concepts. centered phase comes before formal explanations and d definitions of tthe concept are presented by the teacher.
Explain
This phase follows the exploration phase and iss more ore teacher-directed. teacherteache Students are initially encouraged to draw on their learning experiences and earning ex e oncept ept through explanations e demonstrate their understanding of the concept and he opportunity pportunity to t demonstrate discussion. After the students have had the their understanding of the concept, the formal e teacher cher then introduces in definitions and scientific explanations. also clarifies any s. The teacher eache al erged during the th Explore phase. misconceptions that may have emerged
Elaborate
In the Elaborate phase, students nts refine ne and consolidate co c their acquired knowledge and skills. Opportunities for students to further rtunities nities are provided pro apply their knowledge and skillss to new situations in order to broaden si and deepen their understanding rst ng g of the concept. Students may conduct additional investigations, share information and ideas, or apply their ns, sh shar orm knowledge and skillss to other ther disciplines. d disc
Evaluate
This final phase se includes cludes both formal form and informal assessments. These can include concept models, journals as well as more traditional cept maps, physical phys ummative ative assessm assess forms of summative assessment such as quizzes or writing assessments. e encouraged to review and reflect on their own learning, and Studentss are on theirr newly wly acquired knowledge, kn understanding and skills.
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Let’s Do Science
Re ga le du ca tio n
Let’s Do Science is based on the United States Next Generation Science Standards (NGSS). The series consists of full-color textbooks and full-color activity books for Grades K to 6.
Need and
Let’s Do Science engages students with a highly visual al presentation of the disciplinary core ideas in the textbooks xtbooks books and places an emphasis on applying scientific knowledge nowledge ledge using NGSS practices through numerous scientific tific investigations. Let’s Do Science sees engineering ring ass an essential element of science education and tightly d as such is tight integrated into both the textbooks and activity ctivity books.
Anima living food,
Some for fo anim both
The Let’s Do Science textbooks include e the following ffeatures:
Think Deeply
Topic-related questions for group discussion aimed at deepening students’ understanding of the topic.
d In the Field
d uld would wou agine what it woul ma imagine imag an you ima Ca Can C a at What ce?? Wh ace pace sspace? o space to into ravel in ra rav o ttravel like to e like be om from e from ike like lo k lik t look Ea E rth the Earth w d the wo woul would w wa e to walk eel d itt feel uld w would How e? How space space? oo oon oon? moo the moon? on the on
In the past, astronauts have traveled as far as the moon. As science and technologies advance, we into space. Maybe are looking to venture further12 you will be the first astronaut to travel all the way to Mars!
t space is iinto av s into avel a tra tr that travels th n that on son person A person A t. Astronauts o onau on strona str astr a n astronaut. an ed a callled called and s st ear studying years y years ma m ny d many end spe spen spend help us to a auts aut nau on tron tr As Astro ning.. Astronauts aining ai ainin trai training. ou space and the bou abou a e about more learn more system. s our solar objects in our
Engineer It!
Goes beyond inquiry uiry by encouraging students udents to design, model and build olutions to to engineer solutions oblems. defined problems.
A Closer Look
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Chameleons
In the Field
Inspirational sc sciencerelated to ated professions p stir interest rest in sciencerelated careers.
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A Closer Look
Invokes enthusiasm in science by presenting interesting topics beyond the syllabus.
Chameleons are lizards that have spec ial body parts that help them to survive in the place they live.
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105
Amazing Fact!
Re ga le du ca tio n
Interesting facts to bui build interest and enthusiasm. nthusiasm.
Did You Kno Know?
Animals and people drink the water they need.
ds of Animals People
Extra ra information tto build students’ knowledge dents’ know se of the cu base current topic.
People and land animals breathe in the air around them. Some animals, like fish, are able to get the air they need from water.
als and people are things. They need water and air.
e animals eat plants ood. Others eat other als. Some animals eat plants and animals.
How do you get the things you need from day to day.
Try This!
Optional ptio hands-on activities to be conducted activ in groups or at home.
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Science Words
roots stem leaves flowers fruits fur
2. Describe two ways roots help
feathers scales lungs gills respond
4. Copy and complete the e tab table. Body Covering Anim ima all 1 Hair or Fur
Review
1. Use the words in the box fruit
roots
stem
(a)
a plan nt.t.
3. True or false. (a) The roots hold the seeds for the plant. (b) Leaves use water, air and sunlight to m make food for the plant.
to label the picture. leaves
Fe Feathers
flower
(d) (d
Animal 2
AB Activity
Links students to the Let’s Do Science Activity Book at the appropriate juncture.
Scal ales es or Shel Sh l
5. Which body y part do fish f use
to breathe in water? 6. Desc scrib ribe e one way an animal can c respond to changes in its surroundi ngs.
(b)
7.
(e) They have a long, stick y tongue that(c)they shoo t out to catch food such as insec ts.
Describe how a wire fenc e is similar to the blackberry bush.
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Chameleons have curle d tails which help them to hold on to tree branches.
Some chameleons can change the color of their skin. This helps them to blend in with their surro undings and avoid being spotted by predators such as birds .
Review
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Topical questions at the end of each chapter for formative assessment.
Discussion
Topic-related questions and situations for class discussion to build a deeper understanding of topics.
Science Words
Lists the essential science vocabulary covered in each chapter.
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Contents
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Unit 6 – Forces and Motion D Describing Motion W What Is a Force? W What Forces Can Do R view Review
Unit 7 – Matter
I Matter? tter? ter? What Is M Statess of Matter hanging nging Matter Matte Ma Changing ew w Review
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2
4 8 14 18
20 22 28 36 40
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Unit 8 – Sound
What Is Sound? Describing Sounds Making Sounds Review
Unit 9 – Light
Light and an Dark ark Sources es of Light ing g Light Using g t and Sh Light Shadows Materials Light ght and Mat M Reflect fle ecting L Reflecting Light R Re evie vie ew w Review
44 48 56 66
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72 76 80 88 94 9 10 100 10 104
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How can we describe the ways things move?
In this chapter hapter you will ...
• describe be the position and motion of objects.
pushe and pulls. • identify pushes • describe how forces affect motion. desc
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n
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Forces and Motion
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How are people moving in these pictures?
Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
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Position
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Describing Motion n How can you describe where wh the objects are in the room? ro The place an object ject is located loc lo is called its position. osition tion.. We can c use ds to describe de des different words the position of objects. We can use words like on, under, und above, left un ght. and right.
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ca tio n
When we describe position, we often compare the position of one object to another. Let’s compare the position of objects to the desk.
eft We can say the guitar is to the left e of the desk. The lamp is on the desk. The chair is under the desk. k. AB
Activity 6.1
Try This This!
With a p partner, take turns in describing positions of the p objects in your bje classroom. See if cla your partner can name the objects.
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Re ga le du Motion otion on
Go Online!
Observe and describe things in motion on the NGScience website. QuickCode: Y2C9
When hen some something som moves, its position sition c changes. When an object is in the h process of changing he position, we say it is in motion. posit positio
W can c describe motion in We different ways. diff When you bowl a bowling ball, it rolls in a straight line. On a swing, you move back and forth. On a see-saw, you move up and down.
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Things can move from side to side,, in a circle or a zigzag pattern.
We can also use speed to describe scribe ibe motion. Speed is how fast or slow low something moves.
Try T This!
Go in into your school pla playground. With a partner, describe pa the motion of the things you see.
Some things, like a snail, ail, move slowly. Other things, like ea motorcycle, move fastt or qu quickly. quic AB
Activity 6.2 2
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What Is a Force? ce? When something is in n motion it is because use e a force forc has caused it to o move. A force is a push or a pull. pu A push iss when hen you press something you. hing g away from fr f You use a push to t jump into the air, r, throw a ball or catch atch h it.
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Try This!
ion
Make a list st of yo your daily activities. Group ctivities. Gr the activities as ctivities a pushes, pulls or both. hes, pull
A pull is when you tug something closer to you. ou u. Like Li Lik ke when you tug on a rope ope pe e or or drag a sled in the snow. now. AB
Activity 6.3
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A Closer Look
Gravity Gravity is a force that pulls things down towards the Earth. When you throw a ball into the air, the Earth’s gravity pulls it to the ground.
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The Earth’s gravity stops all the things on Earth from flying off into space!
on
When you jump on a trampoline, you don’t fly off into the air. You are pulled down by the Earth’s gravity.
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Different Forces Think Deeply Which requires the bigger force – moving a cart up a hill or down a hill? Explain your answer.
The size of a force affects how an object moves. You can use a mall and small force to move a small light object – like the e force used use to our table. push a pencil on your You need a bigger er force to move o a larger and heavier object. Like d to slide sli a cupboard the force used along a floor. or.
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Big forces can also move things faster and further than smaller forces.
AB
Activity 6.4
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Compare the effect of different sized forces when playing golf. What does a small force do to the golf ball? What does a big force do?
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ati on
Talk about the ways in which forces make a ball move during a game of tennis. ennis.
What Forcess Can Do
When the boy usess a push to hit the mo tennis ball, it will start moving. A force can start an object moving. ving.
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A force can stop a moving object.
Try This! Roll a toy y car down dow a y ramp. How can you sto the use force to stop moving ving car? car
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The girl uses a push to catch the ball. The ball stops moving.
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Go Online!
ge the A force can change direction of a moving oving object. obj
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Observe how forces affect objects on the NGScience website. QuickCode: E2W2
The girl applies forces from different directions as she bounces the ball. The ball moves in different directions.
What are re some ways a an change chan the force can tion of an a object? direction
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A force can speed up or slow down a moving object. AB
Activity 6.5
Engineer neer It It!
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A push can cause the swing to move faster. A pull can make the swing slow down.
Design and build a all machine machin for a pinball table tennis ball. Use machine to show the machin different ways the diffe can affect the forces c motion of the ball.
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Science Words
push pull gravity
Re ga le du ca tio n
position motion speed force
Review
1. What is a force?
2. List two examples of when en you use u a push. 3. List two examples of when you yo use a pull.
4. Which describes the of an object? he location loca (a) motion (b) speed (c) position
5. Which describes escribes an object in the process of changing g position? positio (a) motion (b) speed (c) (c force f
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Re ga le du ca tio n
6. Which describes how fast or slow an object moves? (a) position (b) speed (c) force
7. True or false. (a) Big forces can cause objects to move further s. and faster than small forces. (b) You need small forces to move he heavy objects.
8. Use the words in the box to complete the com sentences. moving
stop
dire direction
(a) A force can an
slow down
a moving object.
(b) A force can star start an object (c) A force change the ce can c moving objec object.
.
of a
can cause an object to speed up or (d) A force f .
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Matter
ca tio n
7
In this chapter you will ...
• describe the properties of matter.
ses. • identify and describe solids, liquids and gases. • describe how matter can be changed.
Re
er. • describe how heat can change matter.
What is matter? How can we describe and sort matter?
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ca t
Whatt are some so ways matter can change? Go Online!
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Access interactive content relating to this topic on the NGScience website. ngscience.com
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What Is Matter?
du ca tio n
Matter is what all thingss are re made of. All of the objects jects ts in your classroom are matter. atter. Water and air are matter too. Even you are matter. atter. ter. What different erent kinds kin of matter can you see in cture? the picture?
AB
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Activity 7. 7.1
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Mass is the amount of matter in an object. We can compare the mass of different matter using a balance.
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All matter has mass and takes up space.
The ball than the all has more mass m toy elephant. What matter is in your classroom? How can you cla describe the matter? d
Try This! Use a balance to compare the mass of different objects in your classroom. Order the objects from the most mass to the least mass.
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Describing Matter
Try This! Close your eyes. Have a classmate hand you an object. Use your sense of touch to describe the object. Can you guess what it is?
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We can describe matter in ur senses. ense different ways using our
We can describe how ow matter ng g its color, shape looks by observing and size. o describe h We can also how matter tter can be rough r feels. Matter or smooth.. It can be hard or soft. h wels are soft and blue. The The towels bowling owling ng ball is i smooth and hard. AB
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Activity 7.2 A
Re g
What words can you use to describe these objects?
In small groups, gro describe objects in your the obje classr classroom. Compare your descriptions with yo other groups. t 25
Re ga le du c Sorting ng Matter Matte
Try This!
Empty your pencil case onto your desk. Sort the objects in different ways. Tell your classmates how they are sorted.
Go Online!
Watch how matter e sorted on the th can be cience websit NGScience website. QuickCode: Code N4S6
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We can an sort or group g matter based ways they are similar. sed on wa way
The e shirts and a candy have been sorted rted ted by color.
du ca tio n
These toys have been sorted d by how they feel – hard toys and soft toys. Activity 7.3
R
AB
Sort the things around you. Tell T e how you sorted them. 27
States of Matter Matte Matter can n be class classified by its state or form. There are three states – ates of matter m solids, and gases. ids, liquids a
Solids Solid objects on your desk The o are solids. Solids have a shape of their own. The sh amount of space a solid takes up does not change.
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The shape and amount of space e taken up by a solid does not change when it is moved from m one container to another.r. When you move your pencils ncils from your pencil case e to your desk, the pencils do not ot change. cha
ga l
What are some solids s in your classroom? ssroom? How can ell they are ar solids? you tell
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Liquids
Try This!
R
Pour water into containers of different shapes and sizes. Describe how the shape of the water changes.
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du ca tio n
Pour some water from a bottle ottle into a glass. How does the water change?
n the liquid state. Water is matter in ave a shape sha of Liquids do not have their own. Liquids quidss flow to take the he container containe they are in. shape of the When water from a er is poured pou e into a glass, glass glas it flows to take bottle the shape ape p of the th glass. g
Think Deeply
Re ga le du ca tio n
Sand flows ws and changess shape when w it moves ves between betwe containers. tainers. Is sand a liquid? solid olid or liqu liqui uid?
Milk, oil and dish soap are also liquids.
What are some other her ou tell liquids? How can you they are liquids?
AB Activities 7.4 7 – 7.5 5
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Gases
Air is a mixture of different gases. The main gases are called nitrogen and oxygen.
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Did You Know?
What happens to a balloon oon n when you blow air into it? Air is a gas. A gas iss a state of matter that does not have a set sprea out shape or size. A gas spreads to fill the container tainer er it is in. in
ati on
When you blow air into a balloon, the balloon changes shape and gets bigger as the air spreads out. Discuss what happens to the air in a balloon when the balloon bursts. AB
Activities 7.6 – 7.7
Go Online! ne!
Explore the different matter on the states of m NGScience website. NGScie QuickCode: H1W3 QuickCo
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Changing States of Matter
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A Closer Look
uc a
Ice is water in n a solid state. When ice is heated, ated, becomes it melts and beco omes liquid water. wate If water is heated, it also ch changes hanges state – it evaporates aporates porates into a gas called water vapor.
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What happens ppens when wh apor is cooled? co water vapor
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n Wh water vapor When W cools, it changes c back into liquid water. This process is called condensation. When the liquid water is cooled, it will freeze and change to solid ice.
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Changing Matter
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Reversible Changess
W can change matter We ter in many ways. We change modeling clay way cla c when we use pushes, hes, pulls and an twists tto change e its shape.
the modeling We can also o change hange th to its clay back b ts original origina shape.
Re g
A change nge to matter matt that can mat be changed hanged anged back bac ba is called a reversible versible sible change. cha ch
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le du ca tio n
H t can change Heat h matter tt too. When heat is added to a solid such as ice, it melts into water. When something g melts, it changes from a solid to a liquid.
R
When water is cooled, ed, it e again. freezes into solid ice When something g freezes, ezes,, ezes it changes from m a liquid liqu liq li to a solid.
Is melting butter a reversible change? How could you find out? c h 37
Irreversible Changes Go Online! Discover more about changes to matter on the NGScience website. QuickCode: U8L5
Think Deeply What change takes place when you make orange juice? Is the change reversible or irreversible? Explain your answer.
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Sometimes matter is changed ged and cannot be changed back. ed These changes are called irreversible changes. es. reversibl Heat can cause irreversible changes. When you cook coo a raw changes Cooling the egg, the egg changes. hange it back to a egg will not change raw egg again. gain.
Cutting a sheet of sib ble change. cha paper is an irreversible er cannot cann be The pieces of paper changed back into a sheet of paper. sh
Re g
n ir Burning iss al also an irreversible change. When you u burn a piece of paper, Th ash cannot be it turns to ash. The ged back to a piece of paper. changed AB
Activities ctivi 7.8 – 7.9
W What are some other ways matter can change? Are the changes reversible or irreversible? 39
Science Words
Review
reversible change melt freeze irreversible change
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matter mass solid liquid gas
1. True or false. gs are made m (a) Matter is what all things of. nt of space matter takes up. (b) Mass is the amount ss and ta (c) All matter has mass takes up space. describ each object. 2. Use two words to describe
Re g
a) (a)
(c)
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(b))
(d))
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3. Use the words in the box to complete the sentences. gases
liquids
solids
(a) Water and milk are examples off (b) (c)
.
have a shape off their own. ow
spread out to o fill the c container
they are in.
4. What happens to solid when it is heated? d matter w d matt 5. What happens to liquid matter when it is cooled? 6. Use the words in the he box to complete the sentences. le irreversible
r reversible
(a) Freezing water is a zing wate
ooking an e (b) Cooking egg is an (c) Melting chocolate is a (c d) Chopping Ch (d) wood is an
change.
change. change. change. 41
Sound
n
8
ed uc at
In this chapter you will ... • describe how sounds are made. • describe sounds around you. • list ways people use sound.
Re ga
What causes sounds? ds? How can you describe ribe sounds? sou
Go Online! line!
Access interactive ctive ating to content relating pic on the this topic cience websit NGScience website. gscience.com ngscience.com
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ca tio n
Try This!
R
Stretch ch an elas elastic d over a plastic p band container. P Pluck the elastic band to make different sounds. What do sounds you o observe?
How do people use sound? 43
Try This! Talk about the different sounds you hear from day to day. Classify them as sounds in nature and sounds made by people.
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What Is Sound? Close your our eyes and listen. What sounds ounds can you hear?
Sound d is a form of energy we hea sounds using our hear. We hear earss and sen sense of hearing.
What Causes Sounds?
Touch the strings as they make a sound. What do you feel? Sound is made when objects ve vibrate. Vibrate means to move back and forth very quickly. Activity 8.1
Use different objects o our classroom classro in your sounds. to make sou Describe tthe sounds partner. Talk to a part what makes about w the ssound.
Re
ed
AB
Try This!
ca tio n
Strum the strings of a guitar. What do you hear? What do you see?
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R
Make some sounds with different musical instruments. What part of each instrument vibrates to make sound? Describe how you are able to hear the sounds made.
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Sound and Vibrationss When an object vibrates, s, it causes cause rate too. too the air around it to vibrate
ca tio n
Try This!
We hear sounds when hen the ches es our ears. ear ea vibrating air reaches AB
Activity 8.2 2
AB Activities 8.3 – 8.4
Think Deeply Can sound nd travel trave h liquids and an through s? Conduct Conduc an solids? experiment eriment to out! find out
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Sounds can also cause materials to vibrate. When the child talks into the tin can, it causes the air inside the tin can to vibrate. This causes the string to vibrate too.
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Make sounds by clapping your hands. What do you do to make soft sounds? What do you do to make loud sounds?
ca tio n
Try This!
Describing bing Soun Sounds Volume e
How is the e sound made when a kitten from the n meows different dif d und of a lion’s lion lio roar? sound Sounds can be loud or soft.
Volume is how loud or soft a sound is.
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al ed uc a
The sound of an airplane taking king off is a loud sound. A whisper is a soft sound. nd.
What are some other ud and examples of loud ds? soft sounds? AB
Activity 8.5
Engineer It!
Design and make an instrument that can make loud and soft sounds. What do you do to change the volume of the sounds?
Go Online! On Compa the volume Compare of diffe different sounds on the NGScience website website. QuickCode: V3A6 QuickC
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A Closer Look
Loud Animals! You may think the roar of a lion is loud, but there are other animals that make even louder sounds!
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Blue whales whistle to each other underwater. These whistles tles can be louder than a jet engine! gine! The derwater from sounds can be heard underwater over 800 km away!
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Cicadas are the loudest insects. They make sound using a special part of their body that works like a drum! Their sounds can be heard from over 2 km away!
ed uc
Kakapos are the he loudest birds. They ds. T ooming make a ‘booming’ sound that be at can b heard d from 7 km away!
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Think Deeply
Pitch
ca
Hit the different bars on a xylophone. What can you infer about pitch and the length gth of the th bars?
Sounds ds can be d di different in pitch. Pitch h iss how high hig or low a sound und is. is
The chirp of a bird and the sound of a party whistle are high sounds.
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ca
The sound of a moving truck is a low sound.
al ed
The sound of thunder during ga storm is also a low sound. d
Engineer It! E
Design and make an instrument that can make high and low sounds. What do you do to change the pitch of the sounds?
What are some other gh and examples of high s low sounds? AB
Activities s 8.6 – 8.7
Go Online! Compare the pitch of different sounds on the NGScience website. QuickCode: E8H4
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du ca tio n What sounds do you hear from day to d fro day? Are the sounds sound loud or soft? Are they high or low? to Describe the sounds s a friend. AB
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Activity 8.8
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Describe the sounds made e by the things on these pages. es.
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Making So Sounds Clap p your ha hands. Blow a Bang on pots and whistle. Ba These are just some pans. T Th you can make sound. ways y What are some other ways you make sound? What vibrates to make the sound? AB
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Activity 8.9
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Using Your Voice
Place two fingers on your throat. roat. Use your voice to make a loud eel?? sound. What do you feel? y al cords. cord In your throat are vocal The vocal cords v vibrate ate te and make sound.
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Musical Mus al Instruments Instrum nstru trum We use se many different di types of musical to make sical al instruments instrum instru ound. nd. Sound Soun is made when part sound. vibrates. of the instrument instr ins
Can you spot the way these instruments are the same? 58
Re ga le d
These instruments all ke have strings. They make sound when we cause se the e strings to vibrate. What can you do o to the strings ngs on a guitar to change the sound und that it makes? es? How does es e sound change? ch ge? the
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Trumpets, s, flutes tes and an trombones make sound ound d when we blow into them. Sound when the air S und d is i made m inside de vibrates. vibrates
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ca tio n Go Online!
Some instruments, such as drums rums ms cymbals and xylophones, make ke sound when we hit them.
Listen to th the sounds of different differe musical instruments on the instrum NGScience website. NGS Can you guess which Ca instrument makes in each sound? QuickCode: R3U9
AB Activity 8.10
Engineer It! Design and build your very own musical instrument!
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du ca t Communication nication cation
We use sound und every ever day for communication. munication. ication. We using sound e communicate communic ommun talk, when en we tal ta laugh or cry.
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When you hear the school bell ring in the afternoon, you know ow it’s t’s time to go home. Bells, whistles, horns and d sirens are other ways we use se sound ound for communication. AB
Engineer It!
Can you communicate using sounds without using your voice? Design and build a device that uses sound to communicate with a friend.
Activity 8.11
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Education
Listen and guess the secret sounds on the NGScience website. QuickCode: Q6Y8
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Go Online!
We use sound to learn about ut the world around us. At school, you use sound to listen lis to your teacher. You to ou use sound sou so answer and ask sk k questions. questions ti
Talk about the different ways you use sound at school. 64
uc a
Entertainment
We use sound to have fun!
u listen ten You use sound when you and dance to your favorite te e music. mu music wa You use sound when you watch television or play video o games. gam Activity 8.12 12
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AB
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Science Words
soft pitch high low
Re ga le du ca tio n
sound vibrate volume loud
Review
1. True or false. (a) Sound is a form of energy ergy we hear. (b) Sound is made when objects vibrate. (c) Sound cannot travel avel through throug the air.
u use to observe o 2. Which sense do you sounds? (a) Taste (b) Smell (c) Sight (d) Hearing g 3. Choose a word to complete each sentence. pitch ch
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volume volu
(a)
is how loud or soft a sound is.
(b)
is how high or low a sound is.
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4. Write two words to describe the sound made by the meow of a kitten.
(a)
(b)
be the sound so 5. Write two words to describe made by the roar of a bear.
(a)
(b)
6. List two ways you make sound. (a)
(b)
7. L Listt two w ways you use sound. (a))
(b)
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In the Field
Sound travels very fast. If you become a an n fighter pilot, you could travel faster than the speed of sound!
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ot of of To become a fighter pilot takes a lo lot st learn learn earn a hard work and study. Pilots must lot of science and mathematics cs before befo be forre e they can fly.
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y loud. ou ud. Fighter jets can fly very fast and are very ound d Some jets can move faster than the sound made by the jets!
When n a fighter fightter jet travels faster than sound, it makes a very ve loud sound – much like thunder. sound iis called a sonic boom! This soun
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Light
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Why do we need light? What happens if there e is no light? ligh How do we use light? ht?
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In this chapter you will ... • understand how light helps us to see. • describe and list sources of light. • list some ways people use light.
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• understand how shadows form.
Try This!
Are you able to see an object in darkness? Conduct an investigation to find out!
Go Online! Access interactive content relating to this topic on the NGScience website. ngscience.com
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Light and Dark Light Did You Know? The light from the Sun is very helpful, but it can also be harmful. It can damage your eyes and skin. Never look directly at the Sun and wear sunscreen on sunny days.
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Go outside and look around un nd you. yo ee e What things can you see? You can see the things hings around arro ght. Light Ligh is a you because of light. form of energy. During Durring the th day, the light from the Sun ght fro helps you to see.
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At night, there is no light from the Sun. People use light bulbs, s, re to to flashlights, headlights and fire see the things around them. m.
What things do people use tto o help them see at night? 73
Dark Try This! Can a camera take photographs in darkness? Conduct an experiment to find out!
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In the dark there iss no light. You Y are in darkness.
In darkness you cannot see the th things around you. To see e things in the dark you need to use light.
What things can you use to help you see when there is darkness? 75
ed uc at Sourcess of Ligh Light
Did You Know?
Natural atural S Sources of Light Some sources of light are found ome me sou so in nature. tur They are not made by people. They are called natural peop people sources of light. sou source
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The moon is not a source of light. It does not produce light of its own. You can see the moon because the Sun shines on it.
The Sun, lamps mps and fire are things that give of their own. ve off ff light o Something off light of ething thing that gives g its own n is called a source of light.
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The Sun, stars, fire and lightning g are natural sources of light.
Go Online! Some living things, such as fireflies, can give out light of their own. This amazing ability is called bioluminescence. QuickCode: S5V5
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Artificial Sources of Light Go Online!
e artificial Electrical lights are hey light up our sources of light. They cities, streets and homes at night. d home
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Discover more about artificial sources of light on the NGScience website. QuickCode: R8B6
Many sources of light are made d by people. They are called ght artificial sources of light.
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AB
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Televisions, computer monitors and phone screens give out light. They are also artificial sources of light. Activities 9.1 – 9.2
Think Deeply
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Are fireworks natural or artificial sources of light? Discuss with your friends.
What are some other artificial sources of light? ar How are they used? H 79
Using Light
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Watch a video on the ways we use light on the NGScience website. QuickCode: D7Y7
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ati o
Go Online!
During the day, we use the lightt ee. from the Sun to help us see. How are the people using usin light? What iss the source sou of light?
At night, we use lights to light up our cities, streets and homes.
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What will happen if the lights in the stadium are switched off?
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Headlights produce prod oduc uce light lig to help lig ee at at night. night drivers see
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Lightss also help us to see als lso h el p u el underwater derwate rwater and an underground.
How are the people using light? What is the source of light? W
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Amazing Fact! A laser is a tool that powerf lets out a powerful m of light. We can beam use lasers to cut metal and other materials! m
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We use light for entertainment and education. Fireworks light up the sky on New Year’s Eve. Theater lights light up the stage during a concert.
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Yo use lights You hts for enter entertainment ente a education ucation ation when whe you and h television, evision play video watch games mes or use a computer. Can you point to the so source of light in these pictures?
AB Activities 9.3 – 9.4
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We use light for communication.
The flashing lights and sirens ns let you know there is an emergency.
Lights can keep you u safe afe n tell from danger. They can you when a train or n is i approaching proac when it is safe to cross cros the road.
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ed uc ati o Cy Cyclists y use lights ts at night to t let le et cars and people eople ple know w y are. re. where they
Brake cars let e lights hts on ca er drivers k kn other know that the slowing down or he e car is slow stopping. pping.
Tal about the different Talk wa ways lights are used for communication.
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Engineer It!
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Lights are used d on signs sign so they d we can ca see them stand out and ark. when it is dark. AB
Design and build a device that can send messages over a distance using light!
Activity 9.5
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Use what you know about light and shadows to build a shadow puppet show stage. Put on a shadow puppet show for your friends.
Light and Shadows ws How Are Shadows Formed? Formed ormed
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Engineer It!
Place your hand nearr a wall and shine a flashlight on n your hand. hand han What do you see?? When an object ect blocks light, lig rmed. The Th dark a shadow iss formed. area you see when you yo y shine a flashlight ht on n your hand ha is dow. a shadow.
What do you notice about the shape of the girl’s hand and the shadow? 88
You see shadows during the day when objects block the lightt from the Sun.
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Activity 9.6
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You see shadows at night when light is blocked from other sources of light.
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Shadow Shape and Size Siz
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Look at the shadows on n this is page. page What object is making g each ach shadow? How do you ou know?
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Light travels in waves. When an object blocks
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The shape of a shadow is always similar in shape to the object blocking the light. What can you do to change ange the size of a shadow?
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Changing Shadows
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Place an object in front of a flashlight and observe the ashlight hlight closer clos shadow. Move the flashlight to the object. Whatt happens tto adow? dow? the size of the shadow?
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Shadows can size. When n change hange siz s oser to an a object, light movess closer ow gets larger. larg lar the shadow
When Wh light moves further from the object, the shadow fr gets smaller. g ge
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eg al ed uc ati o How does your shadow change at different times of the day?
Shadows can also change e in shape. When the flashlight ght ht moves higher, the shadow gets ets shorter. shorter When the flashlightt moves lower, low l the shadow getss longer. lo ger. er. AB
Activity 9.7
Try This!
Find a clear area outside and observe your shadow at different times of the day. How does the shape of your shadow change? What causes the change?
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Light and Materials als What material is each bowl made of ? How are the materials different in the amount of light they allow to pass through?
A material is what an object ect is made of.
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Think Deeply
Materials can be different fferent in th tthe at can pass pas pa amount of light that through them.
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Why are e you able ab to see the block ock in the th glass ntainer cle container clearly?
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Opaque Materials
We cannot see through opaque materials.
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When light hits an opaque object, a shadow is made.
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A material that blocks all light is opaque.
Why can’t you see out o u of the window? 95
Translucent Materials ria
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A material that allowss only nly some light to pass through ough is translucent.
We cannot see ee e clearly through th translucent materials. terials. When light ghtt hits a translucent tra object, is made. t, a light ght shadow sha sh
Why are you able to see through the curtain?
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Transparent Materials
We can see through transparent materials.
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A material that allows light to pass through is transparent.
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When light hits an object made of a transparent material, no shadow is made. e.
Why a are you able to see the m mountain clearly?
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Activities 9.8 – 9.9
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Knowing how how light liight can pass materiia allows us through materials e materials m to choose that are useful for how they eful and and safe s eu sed. are used. A car car windscreen is made of ttransparent rans glass. This allows the driver to see clearly and drive safely. d What are some objects that are useful because they are opaque? The boy’s hat is opaque. This blocks the sunlight from reaching his face. 98
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What are some objects that are useful because they are transparent?
How is the amount off light ht passing passin passi through these objects cts useful?
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Reflecting Light
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You are able to see a source ce of om the light when light travels from source to your eyes. Many things around you are not sourcess of light. How are o see them? th you able to The moon iss not a source of s light. The moon ap appears bright because reflects the light use it reflec from the he Sun. Reflect means to bounce e off.
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You are able to see the hen things around you when they reflect light.
Trace the path the light takes from the Sun to ta the h girl’s eyes. 101
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Som shiny, smooth objects Some reflect light in a way that re allows you to see reflections. The girl is able to see her reflection because the mirror reflects light to her eyes.
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A newly washed car and the still water in a pond have a smooth ooth th and shiny surface. They reflect eflect a lot of light. Dull and rough surfaces aces es do not reflect light well.
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Science Words
material opaque translucent transparent
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light dark source of light shadow Review
1. True or false. (a) Light is a form of energy. y. (b) We can see in darkness. s rce of light. ligh (c) The moon is a source 2. List two natural sources rces of lilight. (a)
(b)
3. List two artificial rtificial sources so of light. (a)
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(b)
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4. Describe two ways you use light during the day. 5. Describe two ways you use light at night.
6. True or false. th (a) A shadow is formed when lightt passes through an object. n object (b) A shadow is formed when an blocks light. 7. Use each word to label the objects objects. opaque
transparent
(b)
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(a)
translucent ucent
(c)
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Re ga le du ca tio n © Blue Ring Media Pty Ltd ACN CN 161 590 496 2013 201 2 - 2021.
This publication wouldd not have been possible without the tireless effort of our production team. Special thanks ks to: Matthew Cole, Daniel Cole, Wang Hui G Guan Joseph Anderson, Halle Taylor Taylor-Pritchard, Sophie Taylor-Pritchard, Tejal Thakur Taylor-Pritcha Varasinun nun Mathanattapat, Kan Kanungnit Pookwanmuang, Saijit Lueangsrisuk
Original Illustrations: Natchanuch Nakapat, graphicsRF, Blue Ring Media and Interact Images trations: Natchanu Royalty-free images: Shutterstock, Adobe Stock ges: Shutte