A company with no inventory buys the following three inventory items: On January 10, the company sells one item for $10. On January 15, the company sells a second item for $10. The company uses a perpetual inventory system. Calculate the company's cost of goods sold under the following inventory costing methods. If required, round your answers to two decimal places. a. FIFO $ 13 b. LIFO $ 15 c. moving Average $ 7