The sum of the error at the end of May is A. 8 B.9 C. 15 D. 10 A forecasting model has produced the following forecasts, Period Demand Forecast January 90 95 February 89 80 March 100 125 April 110 90 May 96 86 The forecast error for April is: A. 10 B.-20 C. 20 D.-10 QUESTION 7 The sum of the error at the end of May is A. 8 B.9 C. 15 D. 10 QUESTION 8 At the end of May the tracking signal would be A.-1 QUESTION 8 At the end of May the tracking signal would be A.-1 B. 0.652 C. 13.8 D. 0.571