Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales dota for DVD players are os follows: The business maintains a perpetual inventory system, costing by the first-in, first-out method. a. Determine the cost of the goods sold for each sale and the inventory balance atter each sale, presenting the cata in the form illustrated in Exhibit 3. Under Fifo, if units are in inventery at two different costs, enter the units with the LowER unit cost first in the Cost of Goods 50 ld Unit Cost column and in the Inventory Unit Cost