i need the answers to D and E

here is the solution for A B C

1) Data collected on the yearly demand for 50-pound bags of fertilizer at Wallace Garden Supply are shown in the following table. YEAR 1 2 2. 3 4 5 6 7 8 DEMAND FOR FERTILIZER (1,000S OF BAGS) 7 6 5 7 10 9 13 15 a) Develop a 3-year moving averages model to forecast sales. b) Develop a 3-year weighted moving averages model in which sales in the most recent year are given a weight of 3 and sales in the other 2 years are each given a weight of 2. c) Use exponential smoothing with a smoothing constant of 0.4 to forecast the demand for fertilizer. Assume that last period's forecast for year 1 is 5,000 bags to begin the procedure. d) Develop a trend line model to forecast sales. You may use excel to find the intercept and slope coefficients of the trend line. e) Which of the developed forecasts (3-year moving averages, weighted moving averages, exponential smoothing, and trend line) would you use based on each of MAD, MSE, MAPE, and bias? Explain your answer. Answer a= Year Demand 3 year moving Forecast 3 year moving Forecast 1.00 7.00 2.00 6.00 3.00 5.00 4.00 7.00 (7+6+5)/3 6.00 5.00 10.00 (6+5+7)/3 6.00 6.00 9.00 (5+7+10)/3 7.33 7.00 13.00 (7+10+9)/3 8.67 8.00 15.00 (10+9+13)/3 10.67 Answer b= Year Demand 3 year moving Forecast 3 year moving Forecast 1.00 7.00 2.00 6.00 3.00 5.00 4.00 7.00 (2*7+2*6+3*5)/7 5.86 5.00 10.00 (2*6+2*5+3*7)/7 6.14 6.00 9.00 (2*5+2*7+3*10)/7 7.71 7.00 13.00 (2*7+210+3*9)/7 8.71 8.00 15.00 (2*10+2*9+3*13)/7 11.00 Answer c= Year Demand Forecast (exponential smoothening) Forecast (exponential smoothening) 1.00 7.00 5 5 2.00 6.00 5+0.4*(7-5) 5.8 3.00 5.00 5.8+0.4*(6-5.8) 5.88 4.00 7.00 5.88+0.4*(5-5.88) 5.528 5.00 10.00 5.23+0.4*(7-5.23) 5.938 6.00 9.00 5.94+0.4*(10-5.94) 7.564 7.00 13.00 7.56+0.2*(9-7.56) 7.848 8.00 15.00 7.85+0.2*(13-7.85) 8.88