Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales for Item 8901 are as follows: January 1 Inventory 49 units @ $20 9 Sale 41 units 13 Purchase 34 units $23 28 Sale 16 units Assuming a perpetual inventory system and using the first in, first-out (FIFO) method, determine (a) the cost of merchandise sold on January 28 and (b) the inventory on January 31 $ a. Cost of merchandise sold on January 28 b. Inventory on January 31