Perpetual inventory using UFO Beginning inventory, purchases, and sales data for DVD players are as follows: The business maintains a perpetual inventory system, costing by the last-in, first-out method. Determine the cost of goods sold for each sale and the inventery balance after each sale, presenting the data in the form illustrated if Exhibit 4 . Under UFO, If units are in inventory at two different costs, enter the inits with the HIGHER unit cost first in the Cost of Goods Sold Unit Cost. column and LOWER unt cost first in the Inventory Unit Cost colurn. Under LFO, if units are in inventory at two different costs, enter the units with the HIGHER unit cost first in the Cost of Goods Sold Unit Cost column and LOWER unt cost first in the Inventory Unit cost column