Perpetual Inventory Using FIFO Beginning inventory, purchases, and sales for Item Zeta9 are as follows: Oct. 1 Inventory 42 units @ $24 7 Sale 29 units 15 Purchase 41 units @ $27 24 Sale 21 units Assuming a perpetual inventory system and using the first-in, first-out (FIFO) method, determine (a) the cost of go inventory on October 31. a. Cost of goods sold on October 24 b. Inventory on October 31