Department j had no work in process at the beginning of the period. 18,000 units were completed during the period, and 2,000 units were 30% completed at the end of the period. the following manufacturing costs were debited to the departmental work in process account during the period (assume the company uses fifo and rounds cost per unit to two decimal places): direct materials (20,000 at $5) $100,000 direct labor 142,300 factory overhead 57,200 assuming that all direct materials are placed in process at the beginning of production, what is the total cost of the 18,000 units completed during the period? a. $283,140b. $90,000c. $16,438d. $193,140