a) Perform a distribution-free test on these data and write a summary of what the result show

b) State briefly why you think a distribution-free test was chosen to analyse these data

Fifteen sets of identical twins were enrolled in a study to measure the effect of air pollution on neonatal mortality. One twin in each set was randomly assigned to the intervention group (renewable energy) or control group (non-renewable energy). At the end of the day, the Air Quality Index (AQI) was recorded, as shown in the data below. Subject id 1 2 3 4 55 6 7 8 9 10 11 222 12 13 14 15 AQI 1 65 67 75 77 69 65 73 78 70 72 73 79 68 73 71 AQI 2 83 75 72 76 78 80 72 81 70 78 7 1 7 70 75 77 71 87