Jan. 20 Purchased Apr. 21 Purchased July 25 Sept. 19 Purchased 330 units $ 4 = $1,320 80 units @ $ 6 = 480 Purchased 220 units @ $ 8 = 1,760 70 units (@ $10 = 700 During the year, The Shirt Shop sold 530 T-shirts for $15 each. Required a. Compute the amount of ending inventory The Shirt Shop would report on the balance sheet, assuming the following cost flow assumptions: (1) FIFO, (2) LIFO, and (3) weighted average. b. Compute the difference in gross margin between the FIFO and LIFO cost flow assumptions.