State hypotheses, identify the claim, find critical values round to three places,compute test value make decision, summarize result

Commute Time to Work A survey of 15 large U.S. cities finds that the average commute time one way is 25.4 minutes. A chamber of commerce executive feels that the commute time in his city is less and wants to publicize this. He randomly selects 30 commuters and finds the average is 24.4 minutes with a standard deviation of 5.3 minutes. At a = 0.01, is he correct? Assume the population is normally distributed