Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales data for DVD players are as follows: November 1 Inventory 53 units at $71 10 Sale 34 units 15 Purchase 22 units at $75 20 Sale 28 units 24 Sale 10 units 30 Purchase 21 units at $78 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 after each sale, presenting the data in the form illustrated. Under FIFO, if units are in inventory at two different costs, enter the units with the LOWER unit cost first in the Cost of Goods Sold Unit Cost column and in the Inventory Unit Cost column.