Please solve this question step by step and solved in a clear way, and show me how you solved it, thanks

my question is similar to the photo I add,l'm not sure what is the incomplete part

10%) Suppose sales for the drivers for the past 12 weeks are: a. Determine the values for simple exponential smoothing with =0.2 for the next 3 weeks. b. Please find the MAPE, MAD, and MSE for simple exponential smoothing and moving average with k=3 for weeks 9,10,11, and 12 . 12. A simple forecasting method for weekly sales of flash drives used by a local computer dealer is to form the average of the two most recent sales figures. Suppose sales for the drives for the past 12 weeks were a. Determine the one-step-ahead forecasts made for periods 3 through 12 using this method. b. Determine the forecast errors for these periods. c. Compute the MAD, the MSE, and the MAPE based on the forecast errors computed in part (b)