Question: A sample of 144 stores stated that a particular brand and model of a VCR retails for a mean price of $375 with a standard deviation of $20.

a) Using the 0.95 degree of confidence, what is the confidence interval?

b) State in the context of the problem, what this confidence interval is telling you.

c) If you were to solve the same problem for a 0.99 degree of confidence, what would change in your equation? You do not actually have to solve the problem, but what would you expect to happen to the interval when you change the level of confidence from a 95% to a 99%?