Using the data of Problem 15.4 on page 600, stored in DomesticBeer , perform either a square-root transformation on the dependent variable (calories) or a square-root transformation on each of the independent variables (percentage alcohol and number of carbohydrates) depending on whether the residuals are normally distributed or vary across X values.

a. State the regression equation.

b. At the 0.05 level of significance, is there a significant relationship between calories and the percentage of alcohol and the number of carbohydrates?

c. Interpret the meaning of the coefficient of determination, r², in this problem.

d. Compute the adjusted r².

e. Compare your results with those in Problem 15.4. Which model is better? Why?