Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales for Item HM46 are as follows: $15 July 1 9 13 28 Tnventory Sale Purchase Sale 62 units 47 units 42 units 23 units $17 Assuming a perpetual Inventory system and using the first in, first-out (FIFO) method, determine (a) 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