At the various activity levels shown, Harper Company incurred the following costs: Units sold a. Rental cost per unit of merchandise sold b. Total phone expense c. Cost per unit of supplies d. Total insurance cost e. Total salary cost f. Total cost of goods sold g. Depreciation cost per unit h. Total rent cost 1. Total cost of shopping bags j. Cost per unit of merchandise sold Required Identify each of these costs as fixed, variable, or mixed. 20 40 60 80 100 $ 36.00 $ 80.00 18.00 100.00 $ 12.00 120.00 $ 9.00 $ 7.20 140.00 160.00 1.00 1.00 1.00 1.00 480.00 480.00 480.00 480.00 1.00 480.00 1,200.00 1,600.00 2,000.00 2,400.00 2,800.00 1,800.00 3,600.00 5,400.00 7,200.00 9,000.00 240.00 120.00 80.00 60.00 48.00 3,200.00 3,200.00 3,200.00 3,200.00 3,200.00 2.00 4.00 90.00 90.00 6.00 90.00 8.00 10.00 90.00 90.00