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 di