Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales for Item HM46 are as follows: July 1 Inventory 65 units @ $23 9 Sale 43 units 13 Purchase 66 units $24 28 Sale 29 units Assuming a perpetual inventory system and using the first in, first-out (FFO) method, determine the cost of merchandise sold on July 28 and (b) the inventory on July 31. a. Cost of merchandise sold on July 28 b. Inventory on July 31