Assume that your stock of sales merchandise is maintained based on the forecast demand. If the distributor's sales personnel call the first day of each month, compute your forecast sales by each of the three methods requested here. a. Using a simple three-month moving average, what is the forecast for September? (Round your answer to 2 decimal places.) b. Using a weighted moving average, what is the forecast for September with weights of 0.10,0.20, and 0.70 for June, July, and August, respectively? (Do not round intermediate calculations. Round your answer to 2 decimal places.) c. Using single exponential smoothing and assuming that the forecast for June had been 128 , forecast sales for September with a smoothing constant alpha of 0.30 . (Round your answer to 2 decimal places.)