Please help with below:

4. Two independent methods of forecasting based on judgment and experience have been prepared each month for the past 10 months. The forecasts and actual sales are as follows: Month Sales Forelcast Forecast 1 660 661 659 2 679 675 677 3 684 680 682 4 670 674 688 5 658 660 664 6 662 658 660 7 650 651 649 8 665 661 665 9 676 674 678 10 680 678 678 a. Compute the MSE and MAD for each forecast. Does either forecast seem superior? Explain. b. Compute MAPE for each forecast. c. Prepare a naive forecast for periods 2 through 11 using the given sales data. Compute each of the following; (1} MSE, (2) MAD, (3) tracking signal at month 10, and [4} 25 control limits. HOW do the naive results compare with the other two forecasts