A company purchased 500 units for $30 each on January 31 . It purchased 550 units for $33 each on February 28 . It sold a total of 640 units for $45 each from March 1 through December 31 . What is the cost of ending inventory on December 31 if the company uses the first - in, first - out (FIFO) inventory costing method? (Assume that the company uses a perpetual inventory system.) A. $1,680 B. $10,620 C. $13,530 D. $12,300