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Given the following annual demand data, calculate the 3-year moving averages for years 4 to 8. Year Demand 1 58 2 76 3 87 4 91 5 98 6 113 7 167 a. Recalculate the 3-year moving averages using a weighted moving average with weights of 0.6 for the most recent year, 0.3 for the second most recent year, and 0.1 for the third year in past. b. If year 8 demand turns out to be 145, what is the weighted moving average for year 9? c. What would the year 9 forecast be if the weightings were changed to (0.7; 0.2; 0.1)