2. (30 points) To answer this question, use the Excel file named Q2_data. Hint: to answer items (a)-(b), you need to take the following steps: Create an R Script file where you write your codes. Import the data set in to R. Set up a linear regression model in R (according to what youre asked under items (a)-(b)). Get the summary of your model (the outputs). These steps are similar to what you saw for in-class exercises and have done for case study 2 a) (15 points) Use the Excel data to estimate the following regression model. = + 11 + 22 + 3 + y = calories x1 = protein (in grams) x2 = fat (in grams) x3 = carbohydrate (in grams) Write the estimated model based on the regression report. (Hint 1: instead of 1, 2, and 3 in the equation above, use the coefficients reported by R) (Hint 2: Copy and paste the regression report below, make sure that your output is readable.)

b) (15 points) There is data on Weight Watchers (WW) points for each meal in the given set of records. WW is a weight loss program that assigns a numerical score to all meals and food items, and gives you a total number of points to target for a day. WW claims that they their system is elaborate and does not directly count calories. Among the 4 nutrients (fat, protein, carbohydrates, and fiber), which one costs the most in WW points and which the least? How much is the difference? (Hint: compute a regression model, where dependent variable is WW points and the 4 nutrients are independent variables)