1 It is thought that the incidence of asthma in children is associated with the volume of traffic in the area where they live.
Two surveys of children were conducted: one in an area where the volume of traffic was heavy and the other in an area where the volume of traffic was light.
For each area, the table shows the number of children in the survey who had asthma and the number who did not have asthma.
| \cline { 2 - 4 }
\multicolumn{1}{c|}{} | Asthma | No asthma | Total |
| Heavy traffic | 52 | 58 | 110 |
| Light traffic | 28 | 62 | 90 |
| Total | 80 | 120 | 200 |
- Use a \(\chi ^ { 2 }\) test, at the \(5 \%\) level of significance, to determine whether the incidence of asthma in children is associated with the volume of traffic in the area where they live.
- Comment on the number of children in the survey who had asthma, given that they lived in an area where the volume of traffic was heavy.