A B E F G H M P R Willie's Petrol Park Week Sales (1000s of gallons) Billie's Gasoline Grotto Week Sales (1000s of gallons) 1 17 2 21 3 19 123 85 2 84 3 76 Brothers Willie and Billie each own a gas station for the same national chain. As brothers, they are very competitive. They held a contest to see who could do a better job forecasting sales for their station over the course of a year. Willie used all-previous values method; Billie used a two-week moving average method. (15 points) 4 23 5 18 60 16 7 20 8 18 45678 69 54 a. Create the forecasts for each gas station. 80 b. Which error calculation MSE or MAPE would be the best to use in this contest? Why? 100 54 c. Who won the contest? 9 22 9 88 10 20 10 80 11 15 11 60 12 22 12 66