13 Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales for Item ER27 are as follows: August 1 Inventory 43 units $22 9 Sale 28 units Purchase 29 units $24 28 Sale 21 units Assuming a perpetual inventory system and using the first-in, first-out (FIFO) method, determine (a) the cost of merchandise sold on August 28 and (b) the inventory on August 31. a. Cost of merchandise sold on August 28 b. Inventory on August 31