1. The I. Kruger Paint and Wallpaper Store is a large retail distributor of the Supertrex brand of vinyl wallcoverings. Kruger will enhance its citywide image in Miami if it can outsell other local stores in total number of rolls of Supertrex next year. It is able to estimate the demand function as follows.

Number of rolls of Supertrex sold= 20xDollars spent on advertising + 6.8xDollars spent on in-store displays + 12xDollars invested in on-hand wallpaper inventory