Need help solving Question 4

Question : (20 mounts A company sells products in several sales territories, each of which is assigned to a single sales rep. The spreadsheet named Sales contains 25 observations on eight independent variables. A regression analysis needs to be conducted to determine whether a variety of predictor variables could explain sales in each territory. To compute all possible regression models, we could develop 8 one-variable equations, 28 two variable regression equations, and so on. As a matter of fact, a total of 255 different estimated regression equations can be modeled. Next try three advanced regression techniques in StatTools. Enter 0.05 in the p-value to Enter or Leave box. Variable Definition Sales Total sales credited to the sales rep Time Length of time employed in month Poten Market potential; total industry sales in units for the sales territory AdvExp Advertising expenditure in the sales territory Share Market share; weighted average for the past four years Change Change in the market share over the previous four years Accounts Number of accounts assigned to the sale rep Work Workload; a weighted index based on annual purchases and concentrations of accounts Rating Sales rep overall rating on eight performance dimension; an aggregate rating on a 1-7 scale 5 points: With Cell K4 as the upper left hand corner of the output, fit the full regression model (report Regression Table only) using the Stepwise Regression function in StatTools. b. 5 points: With Cell K15 as the upper left hand corner of the output, fit the full regression model (report Regression Table only) using the Forward Selection function in Stat Tools. C. 5 points: With Cell K26 as the upper left hand corner of the output, fit the full regression model (report Regression Table only) using the Backward Elimination function in StatTools. d. 5 points: Did the three different methods reach the same model? If not, apply your managerial judgment to choose one model that you think is the best. State your reasons. Place your answers in Cells K37:T48.\f