A warehouse owner wants to know the average weight of books at his facility. He weighs 18 books and finds that the sample has a mean weight of 9.41 pounds and standard deviation of 2.89 pounds....

A warehouse owner wants to know the average weight of books at his facility. He weighs 18 books and finds that the sample has a mean weight of 9.41 pounds and standard deviation of 2.89 pounds. Construct a 99%confidence interval for the population mean of book weights. Assume the population is normally distributed.


Choose the correct confidence interval and critical value used in the calculation.