Smith Concrete Company owns^n ieady-mix trucks. Each truck can deliver (on average)

—-10,000 cubic yards of concrete per year (considering the truck's capacity, weather, and dis¬

tance to each job). One driver per truck is needed. The labor cost of each driver is $25,000-

per year. Depreciation on each truck averages $20,000. Raw materials (cement, gravel, and so on) cost about $25 per cubic yard of cement.

Required:

1. Prepare a graph for each of three costs: truck depreciation, truck drivers' wages, and raw materials. Use the vertical axis for cost and the horizontal axis for cubic yards of cement. Assume that concrete sales range from 0 to 100,000 cubic yards.

2. Assume that the normal operating range for the company is 80,000 to 90,000 cubic yards per year. How would you classify each of the three types of cost?