Manley Co. manufactures office furniture. During the most productive month of the year, 4,500 desks were manufactured at a total cost of $86,625. In its slowest month, the company made 1,800 desks at a cost of $49,500. Using the high-low method of cost estimation, total fixed costs a. are $61,875 b. are $33,875 c. are $24,750 d. cannot be determined from the data given