Consider the Following Partial Computer Output for a Multiple Regression

Consider the following partial computer output for a multiple regression model. $$\begin{array} { l l l } \text { Predictor } & \text { Coefficient } \left( \mathrm { b } _ { \mathrm { i } } \right) & \text { Standard Dev } \left( \mathrm { s } _ { \mathrm { b } } \right) \\\text { Constant } & 99.3883 & \\\text { X1 } & - 0.007207 & 0.0031 \\\text { X2 } & 0.0011336 & 0.00122 \\\text { X3 } & 0.9324 & 0.373 \\& & \\\text { Analysis of Variance } & & \text { SS } \\\text { Source } & \text { df } & 31.308 \\\text { Regression } & 3 & 9.378\end{array}$$
-Consider the following analysis of variance table from a multiple regression model.Test the model for overall usefulness at