Forecast sales of textbooks for the applicable periods using a two period weighted moving average where the weights are most recent and 2 least recent

Calculate MAD for this approach

Use simple exponential smoothing with alpha = 0.6 to forecast textbook sales . Assume that the forecast for January was for 42 textbooks calculate MAD for this approach

Which method do you recommend ? explain in one sentence

Month

Textbook sales

January

48

February

50

March

42

April

49