Test the four assumptions of multiple regression. Begin with output of the three distribution plots on X1, X 2, and Y and provide visual interpretations of normality. Next, paste the scatterplot matrix and interpret it in terms of linearity and bivariate outliers. Next, paste the zero-order correlations (Pearson r) and interpret it to check the multicollinearity assumption. Finally, paste the plot of standardized residuals by predicted residuals and interpret it to check the homoscedasticity assumption