Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales for Item Zeta9 are as follows: Oct. 1 Inventory 63 units @ $21 7 Sale 50 units 15 Purchase 71 units @ $24 24 Sale 20 units Assuming a perpetual inventory system and using the first-) in, first-out (FIFO) method, determine (a) the cost of the goods sold on October 24 and (b) the inventory value on October 31. a. Cost of the goods sold on October 24 b. Inventory value on October 31