Sales of industrial vaccum cleaners at R. Lowenthal supply Co. over the past 13months are as follows: Sales ( $1,000s)/ month 11- Jan. 14- Feb. 16- march 10-april 15-may 17-june 11-july 14-august 17-sept. 12-oct. 14-nov. 16-dec. 11-jan.

a)using a moving average with three periods,determine the demand for vaccum cleaners for next feb.

b) using a weighted moving average with three periods, determine the demand for vaccum cleaners for February. Use 3,2, and 1 for the weights of the most recent, second most recent, and third most recent periods, respectively. For example, if you were forecassting the demand for Feb., November would have a weight of 1, December would have a weight of 2, and January would have a weight of 3.

C) Evaluate the accuracy of each of these methods.

D) What other factors might R. Lowenthal consider in forecasting sales?