Answers for Practice Sets

Dear Dayton Public Schools Student,

Congratulations on your completion of the MasteryPrep ACT After-School Prep Classes! These classes will help you in your upcoming ACT Exam. Now that you have completed the courses you may take your Student Workbook home with you to review the lessons and most importantly the practice sets. Make sure you time yourself when attempting these sets as they will further prepare you for the exam.

The times are as follows: English – 2 min per set Math – 5 min per set (One min per question) Reading – 6 min per set Science – 5 min per set Also included with this packet are the answers, and explanations for all the questions in the practice sets. Be sure to attempt the sets yourself, while being timed, before you look at the answers to check yourself. If you have any questions, please email your instructor, and he or she will provide any additional help you require.

Good Luck!

MasteryPrep Ohio Team

Lesson 1 - Reading Charts an d Graphs

ACT Practice 1.

The correct answer is C. Look at Figure 1 to fmd information about the brass wire. The wire is represented by a dashed line, second from the top. At 60°C, this line hits just above they-axis value 1.0 so the wire expanded about 1.1 mm.

sooc is iron, however it is not an answer option. The next line is nickel. Out of the given options, at 80°C, nickel has the lowest value.

2.

The correct answer is G. Look at Figure 1. The line with the lowest value at

3.

The correct answer is D. Look at Figure 2. At 50°C, three of the lines are below the 1.0 mL mark: water, salt water, and glycerol.

4.

The correct answer is H. Look for the highest val ue in Figure 1. This is shown in the line labeled aluminum, where at 120°C, the expansion is approximately 2.7 mm .

5.

The correct answer is A. Look for the lowest value in Figure 2 at 60°C. This is shown in the line labeled water, where the value is approximately 0.4 ml.

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ACT Practice 6.

The correct answer is G. Look at Table 1, in the column labeled Endangered and the row labeled freshwater fish. The value given is 16.

7.

The correct answer is D. In Figure 1, look at each region listed in the answer choices and compare the black bar (1993 - 1994) to the grey bar (2002- 2003) for each one. In region B average population drops from around 50 rabbits in 1993- 1994 to 0 in 2002- 2003. Region C drops from about 620 to 190 rabbits. Region D drops from about 100 to 50 rabbits. Only in Region F is there an increase, from around 180 to 190 rabbits.

8.

The correct answer is G. Look at Table 1 in the columns labeled Endangered and Vulnerable to fmd a value that is the same in both. This occurs in the row labeled bird, with 27 in each column.

9.

The correct answer is A. Look at Table 1 in the section labeled invertebrate and the co lumn labeled Vulnerable.

Excluding the rows labeled insect land/freshwater decapods, and land/freshwater snails, the remaining species under other total 3.

10. The correct answer is J. In Region C of Figure 1, in the black column that corresponds to 1993- 1994, the population of rabbits is just over 600, or about 620.

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Lesson 1 -Reading Charts and Graphs

ACT Practice 11. The correct answer is A. Figure 1 shows glucose levels based on the time of day. The highest peak of glucose (the solid line) occurs at about 8:30AM. 12. The correct answer is H. In Figure 2, the highest peak for th e glucose levels of a normal person (the solid line) occu rs 1.5 hours after a meal.

13. The correct answer is B. In Figure 2, the solid line that represents the blood glucose levels of a normal person after a meal increases across the region from 0 to 1 hours.

14. The correct answer is G. In Figure 1, the lowest level of the solid line occurs at 7 AM, when the value is just above 4.0 mmoi/L, or about 4.25 mmoi!L. 15. The correct answer is D. In Table 1, the lowest value in the column labeled Glucose is 2, which corresponds to the row labeled fat in the Organ column .

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Set One Answer Explanations 1.

The correct answer is D. Comparing the available data in Table 1 does not show a clear correlation. Zone B had 209 trapped mosquitoes and 2 dead crows/blue jays, Zone C had 234 trapped mosquitoes but no dead crows/blue jays, and Zone A had the highest number of trapped mosquitoes-429-and the highest number of dead crows/blue jays-4. These three zones increase in the number of mosquitoes, but the number of dead birds does not increase in a similar pattern.

2.

The correct answer is G. When 38% of the area was covered with water, 234 mosquitos were captured. When 42% of the area was covered by water, the amount of captured mosquitoes decreased to 209.

3.

The correct answer is A. Compare the increase of cases that included neurological complications. The number of deaths also increased. Compare the increase of cases that did not include neurological complications. The number of deaths also increased here.

4.

The correct answer is F. Each time the percentage of an area with standing water increased, the percentage of households with at least 1 case of West Nile virus also increased.

5.

The correct answer is D. When the number of dead crows and blue jays is put in order from 0 to 4, the corresponding percentage of households in wh ich one or more people were infected by the West Nile virus is 46, 21, 42, 32, and 60, that is the values decrease, increase, decrease, increase, etc.

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Lesson 3 -Variables and Mathematical Relationships

Set Two Answer Explanations 6.

The correct answer is F. The g-force felt by the sample increased only because for each size rotor, an increase in speed was always associated with an increase in g-force compared to the same sized rotor at a lower speed.

7.

The correct answer is A. According to Table 1, the sample that was 9 em from the center of the centrifuge and experienced a g-force of 906g was spun at a speed of 3,000 rpm . A sample placed 4 em from the center would experience the same g-force at 4,500 rpm, which is an increase in speed.

8.

The correct answer is H. In Figure 1, the dashed line that represents Tube 2 has an overall negative slope, which means absorption decreases as time increases.

9. The correct answer is D. In Figure 1, both lines that represent Tubes 1 and 2 have an overall negative slope, which means that absorption decreases as time increases.

10. The correct answer is H. According to the passage, blue DC PIP oxidizes and turns colorless which is used to record the absorption. As time increases and absorption slows down, the DCPIP's concentration of blueness decreases, making choice H the correct answer.

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Set Three Answer Explanations 11. The correct answer is D. Andesite is the second layer of rare earth in Figure 1. Sm and Eu are listed along the x-axis of the f1gure. Tracing the shaded region between those two points shows a decrease in content.

12. The correct answer is F. Between 4 and 12, all the slopes in Figure 3 are positive, which means that all of them are increasing.

13. The correct answer is A. On Figure 3, the slopes for volcanic activity and total number of cold events are identical, which means they are correlated . Choices B and D are incorrect because the slope for total cold events is never constant unless the slope for volcanic activity is also constant. Choice C is incorrect because it states that there is no relationship between volcanic activity and cold events.

14. The correct answer is G. In Figure 1, the shaded region that represents rhyol ite has an overall decrease in thickness between La and Nd. Choices H and J can be eliminated because they say rhyolite decreases. Andesite decreases in thickness, which eliminates choice F. Choice G is correct because it agrees with the information in Figure 1.

15. The correct answer is C. Plugging in a couple of numbers gives the correct answer. When Zr is at 100, Nb is between 5 and 1 0. 1 00 divided by 12 is 8. Choices A, B, and D are incorrect because when 1 00 is factored in for Zr, none of the answers equal the placement of Nb on Figure 2.

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Set One Answer Explanations 1.

The correct answer is A. Choices B and D are incorrect because according to Scientist 2, the normal force between an object and a surface does not change. Choice C is incorrect because the coefficient of kinetic friction is lower than the coefficient of static friction, not higher. Choice A is correct because the coefficient of kinetic friction is lower than the coefficient of static friction, dropping th e frictional force between an object and a surface.

2.

The correct answer is H. To determine the coefficient of static friction, use the equation F = 1J 8 Fw

0.8 = 1-ls 3.

The correct answer is C. According to Scientist 2, the coefficient of static friction between a wet road and a tire is 0.2.

Multiply 0.2 by 3 to determine the coefftcient of static friction between wood and concrete.

4.

The correct answer is J. According to Scientist 2 and the information listed in Tables 1 and 2, static frictional force is determined as the product of the coefficient of static friction and the normal force. If the static frictional force is one tenth of the normal force, the coefficient of static friction must be 0.1. If the kinetic frictional force is half of the static frictional force, the coefficient of kinetic friction must be 0.05.

5.

The correct answer is C. Using Equation 2 to solve for the coefficient of static friction, you must divide the frictional force by the normal force. This creates a ratio of frictional force to normal force. The wood/ice combination has the lowest coefficient of force because it has the smallest ratio of frictional force (0 .5) to normal force (1 0).

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Lesson 8- New Data and Predictions

Set Two Answer Explanations 6.

The correct answer is H. Choices F and G are incorrect because Student 1's hypothesis states that the potential work a spring can do is based on the stretch or compression of the spring, not on the stiffness of the spring . Choice J is incorrect because decreasing a spring's stretch or compression would decrease the amount of work that the spring is able to do. Choice H is correct because increasing the stretch or compression of a spring would increase the work of that spring.

7.

The correct answer is A. Choice B is incorrect because it states that k (the constant stiffness of the spring) is smaller in the new spring, not larger. Choices C and Dare incorrect because x (the distance the spring is stretched) is the same during the experiment. Choice A is correct because the question states that as the stiffness of the spring increases, so does the value of k.

8.

The correct answer is J. Choices F and G are incorrect because the spring will remain still until a force is exerted upon it to make it move. Choice H is incorrect because the potential energy will remain the same because the spring and cart have no potential for movement until a force is acted upon the spring . Choice J is correct because the cart cannot move until a force is exerted upon the spring.

9.

The correct answer is C. Choices A and B are incorrect because there will be more kinetic energy in the spring and cart system due to the increase in potential energy of the spring as it is stretched. Choice D is incorrect because the potential energy will increase as the spring is stretched. Choice C is correct because the spring will exert greater potential energy as it is stretched beyond the equilibrium point. This potential energy will be converted to kinetic energy once the spring is released.

10. The correct answer is F. After the f1rst 15 seconds, all of the potential energy would convert to kinetic energy. After the next 15 seconds (30 seconds total), the kinetic energy would convert back to potential. After the next 15 seconds (45 seconds total), potential energy would convert back to kinetic, and after the next 15 seconds (60 seconds total), the kinetic energy would convert back to potential again. In these 60 seconds, energy has changed from potential to kinetic energy twice.

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Lesson 8- New Data and Predictions

Set Three Answer Explanations 11. The correct answer is C. The coefficient of static friction of lead and cast iron is between the coefficient of static frict ion of the brick/wood combination and the car tire/grass combination. Therefore, we can anticipate that the frictional force results would fall between these two combinations on Figure 2 as well.

12. The correct answer is H. The combination with the lowest coefficient of static friction will also have the lowest frictional force. Figure 3 shows that Unknown 3 has the lowest line indicating frictional force, which means that it also has the lowest coefficient of static friction.

13. The correct answer is A. Choice B is incorrect because the normal force would not be affected by the use of a lubricant. Choices C and D are incorrect because the frictional force must be deceased in order for the materials to slide against each other with only half of the force required. Choice A is the correct answer because a lubricant will decrease the coefficient of static friction between two materials and decrease the subsequent friction of force.

14. The correct answer is G. When the normal force of the horseshoe/rubber combination is 50 N, the frictional force is 32.8 N, falling between the brick/wood and car tire/asphalt combinations at 49 N. When the normal force of the horseshoe/rubber combination is 150 N, the frictional force is 95 N, which also falls between the values for the brick/ wood and car tire/asphalt combinations at 147 N. Thus, the coefficient of static friction for horseshoe/rubber would also fall between the coefficients of static friction for brick/wood and car tire/asphalt.

15. The correct answer is A. The coefficient of friction for chromium/chromium is around 0.42 because the coefficient of the carbon/steel combination is 0.14, and chromium/chromium is three times as much. To fmd the frictional force, use the formula in the Chief Engineer's paragraph to multiply the coefficient of friction (0.42) by the normal force (50).

The answer is 21 N.

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Set One Answer Explanations 1.

The correct answer is B. The passage states that chromosomes with deletions are shorter than normal chromosomes.

Only choice B shows a normal chromosome with a shorter chromosome beside it.

2.

The correct answer is F. Based on Table 1, the incidence rate of trisomy 21 is the highest and the incidence rate of trisomy 18 is the lowest, which is represented in choice F.

3.

The correct answer is A. Trisomy 21 has the highest incidence rate and the highest survival rate, and trisomy 18 has the lowest incidence rate and the lowest survival rate . Thus, the graph should show a positive slope, increasing in both survival rate and incidence rate.

4.

The correct answer is F. The passage states that chromosomal duplications have an excess of genetic information and are longer than normal chromosomes. Only choice F shows a normal chromosome and a longer chromosome beside it.

5.

The correct answer is D. Based on the table, the survival rate of trisomy 18 is the lowest, the survival rate of tri somy 21 is the highest, and the survival rate of trisomy 13 is in the middle. This is represented by choice D, which also shows the correct values for each survival rate as listed in the table.

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Lesson 9- Creating Figures

Set Two Answer Explanations 6.

The correct answer is G. According to Figure 1, the schist layer is represented by diagonal dashes. The bottom of this layer for Sites 1, 2, and 3 is approximately 1,770, 1,790, and 1,71 0, respectively. The best representation of this data is in choice G.

7.

The correct answer is C. In Figure 1, sandstone and marble are separated by numerous other layers, so choice A can be eliminated. Siorite and sandstone are also separated by many layers, which eliminates choice B. Choice D is also incorrect because conglomerate and gneiss are not stacked on top of each other. Schist is stacked on top of marble, so choice C is correct.

8.

The correct answer is F. In Table 2, as the lower limit decreases, so does the upper limit. This is a direct correlation.

Choices G and J can be eliminated because they do not have a positive slope. Since the lower and upper limits decline at about the same rate, choice C is not the best representation. Choice F is correct because it best represents the relationship between the lower and upper limits decreasing and increasing.

9.

The correct answer is D. Table 3 shows the limits of the marble layer are between 1,680 and 1,780 m. Figure 1 represents marble with jagged connected lines. Only choice D shows this marble representation extending below 1,700 m, so it is correct.

10. The correct answer is G. According to Table 1, the upper limit of igneous rocks is 1,960. In Table 2, the upper limit of sedimentary rocks is 1,970, and in Table 3, the upper limit of metamorphic rock is 1,800. These numbers correspond to the graph shown in choice G.

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Set Three Answer Explanations 11. The correct answer is A. The question asks for plant growth, which can be found in Table 1, in the highest vegetation column. The emergent layer has the highest vegetation, at 200 ft, so choices B and D can be eliminated (in this bar graph the dark bars represent values). The understory layer has 12 ft of vegetation. Choice C can be eliminated because understory is placed closer to 100 ft than 1 0 ft. Choice A is correct because the graph best represents the data in Table 1.

12. The correct answer is F. The best way to solve these types of questions is look for the highest or lowest value and eliminate any answer choice that contradicts this information. Understory is the only layer with very high humidity.

Choices G and J do not reflect this and can be eliminated. Emergent is the lowest, with /ow humidity, which contradicts answer choice H. Only the line graph in choice F accurately represents the data in Table 1.

13. The correct answer is C. According to Figure 1, the shrub layer is the lowest layer of the rainforest, and the understor_ is the next lowest layer. Only choice C correctly marks this area of the rainforest diagram where the Iiana plant would grow.

14. The correct answer is J. According to Table 1, the top tree height for the emergent layer is 200 feet, 130 feet for the canopy layer, and 12 feet for the understory layer. This is shown by the graph in choice J. 15. The correct answer is D. Based on Table 1, as layer height goes down, average temperature goes down. Thus, the two are positively correlated, and the associated graph should have a constant positive slope, eliminating choices A and B. Although the difference in height is dramatic, the increase in temperature is more incremental, which eliminates choice B. Between the remaining two graphs, choice D best represents the sudden jump in height among the rainforest layers.

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