Again consider the sales data from problem 1 above. Again, let 2019 and 2020 be the training period, and let 2021 be the validation period. (a) Calculate moving average (MA) forecasts for the validation period using a window width of 4(w=4). (b) Based on your forecasts in part (a), calculate the errors for the validation period. (c) Assuming you are content with the forecasting or predictive accuracy of this model, find the moving average ( MA(4))
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forecast for 2024 Quarter 1.