The Lakeside Company uses a weighted average process costing system. The following data are available: -O- 20.000 16,000 Beginning inventory Units started in production Units finished during the period Units in process at the end of the period (complete as to materials, % complete as to labor and overhead) Cost of materials used Labor and overhead costs 4,000 $ 35,200 $ 37,400 Total cost of the 16,000 units finished is; Select one: O a. $67.320 b. $72.640 C. $63.360 d. $65.120