Calculator Beginning inventory, purchases, and sales for an inventory item are as follows: Sep. 1 Beginning Inventory 22 units @ $13 5 Sale 11 units 17 Purchase 21 units @ $15 30 Sale 16 units Assuming a perpetual inventory system and the last-in, first-out method: a. Determine the cost of the goods sold for the September 30 sale. $ b. Determine the inventory on September 30