A company purchased 400 units for $40 each on January 31. It purchased 400 units for $30 each on February 28. It sold a total of 470 units for $110 each from March 1 through December 31. If the company uses the last - in, first-out inventory costing method, calculate the cost of ending inventory on December 31. (Assume that the company uses a perpetual inventory system.) O A. $9,900 O B. $13,200 OC. $330 O D. $23,100