Consider the regression model fit to the X-ray inspection data in Exercise 12-11.

Use rads as the response.

(a) Calculate 95% confidence intervals on each regression coefficient.

(b) Calculate a 99% confidence interval on mean rads at 15 milliamps and 1 second on exposure time.

(c) Calculate a 99% prediction interval on rads for the same values of the regressors used in the previous part.