The number of daily calls for the repair of Speedy copy machines has been recorded as follows. (Round all answers to 1 decimal place.) a. Prepare three-period moving-average forecasts for the data. What is the error on each day? b. Prepare three-period weighted-moving-average forecasts using weights of W1=0.5,W2=0.3,W3=0.2. What is the error on eac day? c. Calculate the arithmetic sum of errors and the absolute deviation for both methods