Answer the following questions using the data from Problem 14.50:

a. Calculate the coefficient of determination.

b. Using a = 0.05, test the significance of the population coefficient of determination.

c. Construct a 90% confidence interval for the average customer rating from customers who are on hold for 5 minutes.

d. Construct a 90% prediction interval for the customer rating from a customer who is on hold for 5 minutes.

AppendixLO1