Department S had no work in process at the beginning of the period. It added 12,600 units of direct materials during the period at a cost of $88,200; 9,450 units were completed during the period; and 3,150 units were 40% 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 $56,300 and factory overhead was $9,600.

The total conversion costs for the period were

a. $56,300

b. $46,700

c. $65,900

d. $9,600