The level of pollution because of vehicular emissions in a city is not regulated. Measurements by the local government of the change in flow of vehicles and the change in the level of air pollution (both in percentages) on 12 days yielded the following results:

(a) Make a scatter plot to verify that it is reasonable to assume that the regression of \(y\) on \(x\) is linear.

(b) Fit a straight line by the method of least squares.

(c) Find a 95% confidence interval for the mean change in the level of air pollution when the change in the flow of vehicles is \(30 \%\).

Transcribed Image Text:

Change in flow of vehicles x Change in level of air pollution y 28 22 36 26 15 15 19 18 24 21 18 17 25 21 40 31 63 52 12 8 16 17 21 20