4 1 7 2 8 3 6 5 12 6 7 7 13 8 12 9 8 10 9 11 6 9 4 8 9 The following table shows the actual demand observed over the last 11 years: Year Demand This exercise contains only parts b, c, and d. b) Using the 3-year moving average, provide the forecast from periods 4 through 12 (round your responses to one decimal place). Year 5 6 7 10 11 12 Forecast 0 0 0 c) Using the 3-year weighted moving average with weights 0.20,0.30, and 0.50, using 0.50 for the most recent period, provide the forecast from periods 4 through 12 (round your responses to two decimal places). Year 4 5 6 7 8 9 10 11 12 Forecast Mean absolute deviation for the forecast developed using the 3-year moving average is 2.71 and for the 3-year weighted moving average is 2.76. Based on this information, the better forecast is achieved using the approach 3-year moving average weighted moving average