The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took the customers in the sample to check out was 4 minutes with a sample standard deviation of...

The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took the customers in the sample to check out was 4 minutes with a sample standard deviation of 0.5 minutes. Conduct a test to determine whether or not the mean waiting time of all customers is significantly more than 5 minutes. Use a significance level of α = 0.01.