artment A had 5,000 units in work in Process that were 80% completed at the beginning of the period at a cost of $7,100. During the period, 33,100 units of direct materials were added at a cost of S69, and 35,300 units were completed. At the end of the period 2,800 units were 34% completed. All mate als are added at the beginn ng of the process. Direct labor was $25 200 and factory overhead was S5,600 The cost of the 2,800 units in process at the end of the period if the first-in, first-out method is used to cost inventories was a. $7,698 b. $6,335 C. $5,880 d. $6,789