A company purchased 300 units for $30 each on January 31. It purchased 390 units for $39 each on February 28. It sold a total of 440 units for $40 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.) O A. $7,500 O B. $7,360 O C. $140 OD. $9,750