Use the results of Problem 17 in Section 14.1 to answer the following questions:
(a) Predict the mean annual ROI of all four-year schools whose 2013 cost is $180,000.
(b) Construct a 95% confidence interval for the mean annual ROI found in part (a).
(c) Predict the annual ROI of a randomly selected four-year school whose 2013 cost is $180,000.
(d) Construct a 95% prediction interval for the annual ROI found in part (c).
(e) Explain why the predicted lengths in parts (a) and (c) are
the same, yet the intervals constructed in parts (b) and (d)
are different.