Department S had no work in process at the beginning of the period. It added 14,200 units of direct materials during the period at a cost of $99,400; 10,650 units were completed during the period; and 3,550 units were 36% 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 $57,700 and factory overhead was $9,800. The total conversion costs for the period were

a. $57,700

b. $47,900

c. $9,800

d. $67,500