Penny Inc. uses process costing. All direct materials are added at the beginning of the process. Information about July's activities is as follows: On July 1: Beginning inventories Direct materials cost Conversion costs 850 units, 60% complete $5,000 $4,000 During July: Number of units started Direct materials added Conversion costs added 15,000 $155,000 $83,520 On July 31: Ending inventories 1,600 units, 40% complete Using the FIFO method, the number of equivalent units for conversion costs was Oa. 14,550 Ob. 14,380 Oc. 15,850 Od. 14,400