Department A had 4,500 units in Work in Process that were 71% completed at the beginning of the period at a cost of $6,900. During the period, 29,800 units of direct materials were added at a cost of $65,560, and 31,400 units were completed. At the end of the period, 2,900 units were 25% completed. All materials are added at the beginning of the process. Direct labor was $25,400 and factory overhead was $5,100. The cost of the 2,900 units in process at the end of the period if the first-in, first-out method is used to cost inventories was Oa. $7,908 Ob. $7,144 Oc. $6,762 Od. $6,380