$\hat{y}$ = + $x_1$ + $x_2$ + $x_3$ + $x_4$
 $x_1$ = $x_2$ = $x_3$ = $x_4$ =
 $n$ = SST = SSR =
 MSR = MSE =
 $s_{b_1}$ = $s_{b_2}$ = $s_{b_3}$ = $s_{b_4}$ =
Example 1Example 2