During December, Krause Chemical Company had the following selected data concerning the manufacture of Xyzine, an industrial cleaner: Production Flow Physical Units Completed and transferred to the next department 100 Add: Ending work in process inventory 10 (40% complete as to conversion) Total units to account for 110 Less: Beginning work in process inventory 20 (60% complete as to conversion) Units started during December 90 All materials are added at the beginning of processing in this department, and conversion costs are added uniformly during the process. The beginning work in process inventory had $120 of raw materials and $180 of conversion costs incurred. Materials added during December were $540, and conversion costs of $1,484 were incurred. Krause uses the first-in, first-out (FIFO) process cost method. The equivalent units of production used to compute conversion costs for December were: a.110 units. b.104 units. c.100 units. d.92 units.