This question should be answered using the Carseats data set.

(a) Fit a multiple regression model to predict Sales using Price,

Urban, and US.

(b) Provide an interpretation of each coefficient in the model. Be

carefulsome of the variables in the model are qualitative!

c) For which of the predictors can you reject the null hypothesis

d) How well do the models in (a) fit the data?

e) Include a squared term for Price in the model. What do the results suggest? Evaluate the fit and the forecast accuracy of this model relative to model in 1.

Please include all the R code and R output.