This question should be answered using the Carseats data set from ISLR libray. Please go to ISLR package in R to learn more about the Carseats dataset.

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

Advertising, and Income.

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

careful.

(c) Write out the model in equation form.

(d) For which of the predictors can you reject the null hypothesis

H0 : j = 0?

(e) On the basis of your response to the previous question, fit a

smaller model that only uses Price and Income as the predictors.

(f) How well do the models in (a) and (e) fit the data?