Suppose that variables x2 and x3 are added to the model and the following regression equation is obtained.

LaTeX: \hat yy^ = 16.3 + 2.3x1 + 12.1x2 - 5.8x3

For this estimated regression equation SST = 1550 and SSE = 100.

Use an F test and a 0.05 level of significance to determine whether x2 and x3 contribute significantly to the model.