A textbook publishing company has compiled data on total annual sales of its business texts for the preceding nine years: Year Sales (000): 2 43. 70 3 49. 20 5 55. 30 38.10 51.90 58. 10 7 62.50 8 69.50 74.70 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.) 10 11 12 13 14 Year Forecast 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 + c. Suppose actual sales for the next five years turn out as follows: Year Sales (000): 10 79.10 11 82.40 12 87.10 13 92. 10 14 96.80 Is the forecast performing adequately? O Yes O No B C D E F G H | K L M N 1 2 3 4 5 6 7 8 J 9 74.7 38.1 43.7 49.2 51.9 55.3 58.1 62.5 69.5 10 79.1 11 82.4 12 87.1 13 92.1 14 96.8 A 1 Year: 2 Sales (000): 3 4. Data for Part c: 5 Year: 6 Sales (000): 7 8 9 10 11 12 13 14 15 16 17