Question: Safety researchers, interested in determining whether the occupancy of a vehicle might be related to the speed at which the vehicle is driven, have observed the following speed (mph) measurements for two random samples of vehicles. (Use data file XR12030)

(File XR12030)

a) What are the null and alternative hypothesis for this test?

b) Use ANOVA and the 0.025 level of significance in testing the null hypothesis identified in part (a).

c) For each sample, construct the 95% confidence interval for the population mean.