The amount of time a bank teller spends with each customer has a population mean of 3.10 minutes and a standard deviation of 0.40 minute. If you select a random

sample of 16 customers, 1. What is the probability that the mean time spent per customer is at most 3minutes? 2. There is an 80% chance that the sample mean is less than how many minutes? 3. What assumption must you make in order to solve (Task 1) and (Task 2)? 4. If you select a random sample of 60 customers, there is an 95% chance that the sample mean is less than how many minutes?