Beginning inventory, purchases, and sales for an inventory item are as follows: Sep. Beginning 31 units $14 1 Inventory 5 Sale 18 units 17 Purchase 33 units $16 30 Sale 34 units Assuming a perpetual inventory system and the first-in, first-out method, determine (a) the cost of the goods sold for the September 30 sale and (b) the inventory on September 30. a. Cost of goods sold b. Inventory September 30