Department S had no work in process at the beginning of the period. It added 13,800 units of direct materials during the period at a cost of $110,400. During the period, 10,400 units were completed, and 3,400 units were 35% completed as to labor and overhead at the end of the period. All materials are added at the beginning of the process. Direct labor was $71,858, and factory overhead was $20,862. The total cost of units completed during the period was a. $147,680 b. $199,680 c. $166,400 d. $83,200