A local restaurant does not accept any reservations and only focuses on walk-in customers. The owner of the restaurant wants to find out how many walk-in customers he should plan to have every day. To that end, kept records of the number of walk-in customers for the last 63 days. The average number of daily walk-in customers was 67.3 and the sample standard deviation is 7.1. Construct a 99% confidence interval for the number of customers on a given day.

The lower limit isA

.

The upper limit isB

.