8. Single regression

8.a. Please fit a linear regression model giving post as a linear function of pre from the

"dat_pre_post" data set. Display the coefficients with their p-values. (5 points)

8.b. Please use your work in question 4 and any additional plots you find informative to

address the validity of the model, the coefficients, and the p-values. Please be sure to

address the linearity of the relation between pre and post and the distributional

assumption that the residuals are independent identically distributed samples from a

Normal (0,02) distribution.(15 points)