Drive Train, Inc. instituted a new process in October 2020. During October, 10,000 units were started in Department A. Of the units started, 8,000 were finished, and 2,000 remained in Work-in-Process at October 31, 2020. The Work-in-Process at October 31, 2020, was 100% complete as to material costs and 50% complete as to conversion costs. Material costs of $27,000 and conversion costs of $36,000 were charged to Department A in October. What were the total costs of finished goods assuming Department A uses weighted-average process costing? Select one: a. $56,000. b. $57,120. c. $46,900. d. $53,600.