jakes Roof Repair has provided the following data concerning its costs: Fixed Cost per Month Cost per Repair-Hour Wages and salaries $ 21,300 $ 15.00 Parts and supplies $ 7.30 Equipment depreciation $ 2,780 $ 0.55 Truck operating expenses $ 5,750 $ 1.90 Rent $ 4,650 Administrative expenses $ 3,820 $ 0.70 For example, wages and salaries should be $21,300 plus $15.00 per repair-hour. The company expected to work 2,800 repair-hours in May, but actually worked 2,700 repair-hours. The company expects