department m had 2,200 units 52% completed in process at the beginning of june, 12,600 units completed during june, and 1,600 units 29% completed at the end of june. what was the number of equivalent units of production for conversion costs for june if the first-in, first-out method is used to cost inventories? a.13,064 units b.11,920 units c.10,400 units d.14,664 units