I need help with b, c and d

The following table shows the actual demand observed over the last 11 years: 2 3 4 5 6 7 Year Demand 1 7 8 14 9 10 10 13 11 7 9 5 10 13 7 13 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 4 5 6 7 8 9 10 11 12 Forecast c) Using the 3-year weighted moving average with weights 0.15, 0.35, 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 7 8 9 10 11 12 Forecast d) Mean absolute deviation for the forecast developed using the 3-year moving average is 2.95 and for the 3-year weighted moving average is 3.42. Based on this information, the better forecast is achieved using the approach 3-year moving average weighted moving average E swer boxes