just need part b. and c.

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 0.30,0.40, and 0.30 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 126 , forecast sales for September with a smoothing constant alpha of 0.30. (Round your answer to 2 decimal places.)