Using the sat dataset, fit a model with the total SAT score as the response and expend,salary, ratio and takers as predictors. Perform regression diagnostics on this model to answerthe following questions, and display any plots that are relevant.a. Check the constant variance assumption.b. Check the normality assumption.c. Check for large leverage points.d. Check for outliers.e. Check for influential points.f. Check the functional form of the relationship between the predictors and the response.