Beginning inventory, purchases, and sales for an inventory item are as follows: Sep. 1 Beginning Inventory 24 units @ $12 5 Sale 12 units 17 Purchase 27 units @ $14 30 Sale 18 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