3-31 (Static) A textbook publishing company has compiled data on total annual sales of its business texts for the preceding nine years: Year Sales (000): 40.20 44.50 48.00 52.30 55.80 57.10 62.40 69.00 73.70 Click here for the Excel Data File a. Using an appropriate model, forecast textbook sales for each of the next five years. (Round your intermediate calculations to 3 decimal places and final answers to 2 decimal places.) Year Forecast 10 11 12 13 14. Saved Help Save & Exit Submit 42 b. Compute +/- 2s control limits for the control chart for forecast errors using just data from the original nine periods. (Round your intermediate calculations to 4 decimal places and final answer to 2 decimal places.) Control limits are 0 kipped c. Suppose actual sales for the next five years turn out as follows: Book Ferences Year Sales (000): 10 11 77.20 82.10 12 87.80 13 90.60 14 98.90 Is the forecast performing adequately? Yes No