Time Period Demand 6 years ago 5 years ago 4 years ago 3 years ago 2 years ago Last year 28 21 42 35 56 49 What is this year’s forecast using a three-year moving average? What is this year’s forecast using a three-year weighted moving average, where the weights are .5,.3, .2? A. B. C. What is this year’s forecast using the linear trend method. D. Which forecast method has the smallest Mean Absolute Deviation (MAD), based upon forecasts