Question 3 Data collected on the yearly demand for 50-pound bags of fertilizer at Wallace Garden Supply are shown in the following table. YEAR 1 DEMAND FOR FERTILIZER (1,000S OF BAGS) 4 6 2 3 4 4 5 5 6 10 8 7 7 8 9 9 12 10 14 11 15 a) Estimate demand with a weighted moving average in which sales in the most recent year, next most recent, most distant are given weights of 3,2 and 1 respectively. Compute the MAD, MSE and MPE for this method.(six marks) b)Use exponential smoothing with a smoothing constant of 0.2 to forecast the demand for fertilizer. Assume that last period's forecast for year 1 is 5,000 bags to begin the procedure. Which method do you think is best?. Is this an improvement over the weighted average- use MAD alone( Six marks) c) Use regression analysis to estimate the line of best fit( 4 marks). Forecast the demand for years 12 and 13 (4 marks) where: y=a+bx nxy-xy b= nx - (x) a=y-bx