A sales manager collected the following data on annual sales for new customer accounts and the number of years of experience for a sample of 10 salespersons. Years of Annual Sales Salesperson Experience ($1000s) 80 75 86 96 u u w ww 93 DOYOU A WN 100 117 122 141 10 6 146 The data on y = annual sales ($1000s) for new customer accounts and * = number of years of experience for a sample of 10 salespersons provided the estimated regression equation y = 59.40 + 12.16x. For these data # = 3.8, ) (x - x)' = 31.60, and s = 10.4356. a. Develop the 90% confidence interval for the mean annual sales ($1000s) for all salespersons with four years of experience. ($ (to 2 decimals) b. The company is considering hiring Tom Smart, a salesperson with four years of experience. Develop a 90% prediction interval of annual sales ($1000s) for Tom Smart. ($ ) (to 2 decimals) c. Discuss the differences in your answers to parts (a) and (b). As expected, the prediction interval is much | wider than the confidence interval. This is due to the fact that it is more | difficult v to predict annual sales for one new salesperson with 4 years of experience than it is to estimate the mean annual sales for all salespersons with 4 years of experience