Department E had 4,000 units in work in Process that were 40% completed at the beginning of the period at a cost of $12,500. 14,00o units of direct materials were added during the period at a cost of $28,700. 15,0ooo units were completed during the period, and 3,000 units were 75% completed at the end of the period. All materials are added at the beginning of the process. Direct labor was $32,45o and factory overhead was $18,71o. The number of equivalent units of production for the period for conversion if the first-in, first-out method is used to cost inventories was: a. 14,850 b. 15,650 c. 14,150 d. 14,650