Preston Company manufactures car seats in its Tulsa plant. Each car seat passes through the assembly department and the testing department. This problem focuses on the assembly department. The process-costing system at Preston Company has a single direct-cost category (direct materials) and a single indirect-cost category (conversion costs). Direct materials are added at the beginning of the process. Conversion costs are added evenly during the process. When the assembly department finishes work on each car seat, it is immediately transferred to testing. Preston Company uses the FIFO method of process costing. Data for the assembly department for October 2013 are as follows: (Click the icon to view the assembly department data.) (Click the icon to view the weighted average cost per equivalent unit data.) Read the requirements Direct Materials Conversion Costs Physical Units (Car Seats) 5,200 $ 1,432,600 S 527,280 19,000 Work in process, October 1 (a) Started during October 2013 Completed during October 2013 Work in process, October 31 (b) Total costs added during October 2013 21,500 2,700 $ 4,085,000 $ 2,028,000 (a) Degree of completion: direct materials, ?%, conversion costs, 65%. (b) Degree of completion direct materials, ?%, conversion costs, 80%. Direct Conversion Materials Costs Costs incurred to date Divide by: Equivalent units of work done to date $ 5,517,600 $ 2,555,280 24,200 23,660 $ 228 $ 108 Cost per equivalent unit for work done to date 1. For each cost category, compute equivalent units in the assembly department. Show physical units in the first column of your schedule. 2. For each cost category, summarize total assembly department costs for October 2013 and calculate the cost per equivalent unit. 3. Assign total costs to units completed and transferred out and to units in ending work in process. 4. Explain any difference between the cost per equivalent unit in the assembly department under the weighted-average method and the FIFO method. 5. Should Preston's managers choose the weighted average method or the FIFO method? Explain briefly