19 Sales of Hot-Blast heaters have grown steadily during the past five years, as shown in the following table:

(a) Using exponential smoothing constants of 0.35, 0.65, and 0.95, develop forecasts for years 2 through 6. The sales manager had predicted, before the business started, that year 1’s sales would be 440 air conditioners. Which smoothing constant gives the most accurate forecast?

(b) Use a three-year moving average forecasting model to forecast sales of heaters.

(c) Using linear trend analysis, develop a forecasting model for the sales of heaters.

(d) Which of the methods analyzed here would you use? Explain your answer.