Shanna operates a lounge in an extremely popular downtown convention hotel. the hotel regularly operates around the 80 percent occupancy mark, and its lounge, luigi's, is very often filled to capacity. on weeks when business at the hotel is slower, shanna attempts to build local sales by scheduling a variety of popular bands to play on the stage. she must select one band to play on saturday night, six weeks from now, when the hotel is not busy. she has kept records of the costs and sales volume of the last four bands she has booked