16 8
Nitrogen dioxide is a pollutant found in air. Scientists think that there is a link between nitrogen dioxide levels and the severity of asthma attacks. Look at the graph. It shows data about the severity of asthma attacks in young men. 10 9 8 7 6 relative severity of asthma attack
5 4 3 2 1 0
0 10 20 30 40 50 60 70 80 nitrogen dioxide levels in Îźg / m3
(a) What conclusion can you draw about the link between nitrogen dioxide levels and the severity of asthma attacks? ................................................................................................................................................... .............................................................................................................................................. [1] (b) The data is for men aged between 20 and 40 who live in a city centre. Nick thinks you can use the graph to draw a firm conclusion about nitrogen dioxide levels and the severity of all asthma attacks. Phil thinks more evidence is needed. Suggest who is correct. Explain your answer. ................................................................................................................................................... .............................................................................................................................................. [1] [Total: 2]
Š OCR 2014