Demand for widgets steadily increasing.

year 1 2 3 4 5 6
widgets 45 50 52 56 58 ?

6 years ago it wss predicted that demand in year 1 would be 41 widgets.

a. use exponential smoothing constant of .6 and then .9 to project forecasts for years 2 through 6.
b. use 3 yr moving average to forecast demand in years 4,5, 6.
c. use trend projection method to forecast demand in years 1-6.
d. with MAD as the criterion, which of the four forecasting methods is best