Lorenzo operates a brushless car wash. Incoming cars are put on an automatic, continuously moving conveyor belt. A car is washed as the conveyor belt carries it from the start station to the finish station. After the car moves off the conveyor belt, workers dry it and clean and vacuum the inside. Workers are managed by a single supervisor. Lorenzo's accountant wants to estimate costs in December, when 8,750 cars are expected to be washed. She tried two different methods to estimate December costs, account analysis and high ow, with number of cars washed as the independent variable for both methods. To estimate the cost function parameters using account analysis, she analyzed actual costs in June, when 11,800 cars were washed. Her analysis revealed the following total fixed costs and total variable costs for each cost item Cost Item Variable Cost Total Cost $5,900 $5,900 soap, cloths, and supplies $4,720 $4,720 Car wash labor $30,390 $28,320 Power for conveyor $12,200 $9,440 so Supervisor and cashier $3,300 To estimate the cost function parameters using high she used the following total cost and activity data from July and August: Cost Item July August Soap, cloths, and supplies $1,740 $2,260 Water $6,780 $5,220 Car wash labo $26,360 $33,640 $9,560 Power for conveyor $11,640 $3,150 Supervisor and cashier $3,150 Total $57,470 $46,030 Cars washed 8700 11,300