You are the manager of a restaurant for afast-food franchise. Lastmonth, the mean waiting time at thedrive-through window for branches in your geographicalregion, as measured from the time a customer places an order until the time the customer receives theorder, was 3.7 minutes. You select a random sample of 81 orders. The sample mean waiting time is 3.95 minutes, with a sample standard deviation of 0.9 minute. Complete parts(a) and(b) below.

a. At the 0.05 level ofsignificance, is there evidence that the population mean waiting time is different from 3.7 minutes? State the null and alternative hypotheses.

b. Because the sample size is 100, do you need to be concerned about the shape of the population distribution when conducting the t test in(a)? Explain.