Chapter 11.7, Problem 64E

a.

To determine

Find the residuals for the least squares model.

b.

To determine

Draw a normal probability plot of the residuals.

Interpret the display.

c.

To determine

Plot the residuals versus $\widehat{y}$ and versus x.

Check whether the assumption of constant variance seem to be satisfied or not.

d.

To determine

Find the proportion of total variability which is explained by the regression line.