42%_ 4:54 9. Consider the sales data for Com puter Success given in Problem 7. a. Use a 3-month weighted moving average to forecast the sales for the months April through December. Use weights of (4/8), (3/8), and (1/8), giving more weight to more recent data. b. Use exponential smoothing with a 0.6 to forecast the sales for the months April through December. Assume that the initial forecast for January was $3,200. Start error measurement in April c. Compare the performance of the two methods by using the mean absolute deviation as the performance criterion, with error measurement be ginning in April. Which