18. If Department K had 2,000 units, 45% completed, in process at the beginning of the period, 12,000 units were completed during the period, and 1,200 units were 40% completed at the end of the period, what was the number of equivalent units for conversion for the period, if the first-in, first- out method is used to cost inventories a. 11,580 b. 11,280 C. 13,680 d. 10,000