. The inventory data for an item for September are: Sep. 1 Inventory 20 units at $19 4 Sold 10 units 10 Purchased 30 units at $20 17 Sold 20 units 30 Purchased 10 units at $21 Using the perpetual system, costing by the last-in, first-out method, what is the cost of the merchandise sold for September? $610 b. $600 $590 d. $580 a. c