(12%) Observed weekly sales of ball peen hammers at the town hardware store over an eight-week period have been 14, 9, 30, 22, 34, 12, 19, 23. a. Suppose that three-week moving averages are used to forecast sales. Determine the onestep-ahead forecasts for weeks 4 through 8. b. Suppose that exponential smoothing is used with a smoothing constant of a = 0.15. Find the exponential smoothing forecasts for weeks 4 through 8. [To get the method started, use the same forecast for week 4 as you used in part (a).] c. Based on the MAD, which method did better? d. What is the exponential smoothing forecast made at the end of week 6 for the sales in week 12?