SmartAsset reports that the average weekly earnings for workers who have not received a high school diploma is $493 in 2018. Suppose you would like to determine if the average weekly earnings for workers who have received a high school diploma is significantly greater than average weekly earnings for workers who have not received a high school diploma. Data providing the weekly pay for a sample of 50 workers who have received a high school diploma are available in the file WeeklyHSGradPay. These data are consistent with the findings reported by SmartAsset.

a. State the hypotheses that should be used to test whether the mean weekly pay for workers who have received a high school diploma is significantly greater than the mean weekly pay for workers who have not received a high school diploma.

b. Use the data in the file WeeklyHSGradPay to compute the sample mean, the test statistic, and the p-value.

c. Use α = .05. What is your conclusion? Is this result surprising? Why did these data likely lead to this conclusion?

d. Repeat the hypothesis test using the critical value approach.