Department A had 4,000 units in Work in Process that were 79% completed at the beginning of the period at a cost of $7,700. During the period, 36,800 units of direct materials were added at a cost of $77,280, and 38,500 units were completed. At the end of the period, 2,300 units were 34% completed. All materials are added at the beginning of the process. Direct labor was $25,300 and factory overhead was $5,600. The cost of the 2,300 units in process at the end of the period if the first-in, first-out method is used to cost inventories was Oa. $4,830 b. $6,168 Oc. $5.499 Od. $5,165