Compute the forecasts using mad and decide which is best

Question

The following data are monthly sales of jeans at a local department store. The buyer would like to forecast sales of jeans for the next month, July.

(a) Forecast sales of jeans for March through June using the naïve method, a two-period moving average, and exponential smoothing with an α = 0.2. (Hint: Use naïve to start the exponential smoothing process

(b) Compare the forecasts using MAD and decide which is best

(c) Using your method of choice, make a forecast for the month of July.