Penny, Inc. employs a process costing system. Direct materials are added at the beginning of the process. Here is information about July's activities: On July 1: Beginning inventories Direct materials cost 850 units, 60% complete $5,000 $4,000 Conversion costs During July: Number of units started 15,000 $155,000 Direct materials added Conversion costs added $83,520 On July 31: Ending inventories 1,600 units, 40% complete Using the FIFO method, the number of units started and completed in July was O a. 14,250 Ob. 15,000 Oc. 13,400 O d. 15,740