Following are the data on total hours studied over 2 weeks and test score at the end of the 2 weeks from Exercise 14.21.

a. Determine a point estimate for the mean test score of all beginning calculus students who study for 15 hours.
b. Find a 99% confidence interval for the mean test score of all beginning calculus students who study for 15 hours.
c. Find the predicted test score of a beginning calculus student who studies for 15 hours.
d. Determine a 99% prediction interval for the test score of a beginning calculus student who studies for 15 hours.
Presuming that the assumptions for regression inferences are met, determine the required confidence and prediction intervals.

r 10 15 12 20 8 16 4 22 92 81 84 74 85 80 84