The correct answer is option A... But I dont know how to solve question. I tried so many ways, non of them worked. Thanks!

5. 21 30 Trumpeting Trumpets has the following inventory data: July 1 Beginning inventory 50 units at $120 Purchases 300 units at $112 14 Sale 250 units Purchases 150 units at $115 Sale 240 units Assuming that a perpetual inventory system is used, what is the cost of goods sold for the July 30 sale on a LIFO basis? a. $27,650 b. $28,000 c. $55,650 d. None of the above