Required information [The following information applies to the questions displayed below.) The Shirt Shop had the following transactions for T-shirts for Year 1, its first year of operations: Jan. 20 Apr. 21 July 25 Sept. 19 Purchased Purchased Purchased Purchased 420 units 150 units 230 units 80 units @ $ 9 = $3,780 @ $ 10 = 1,500 @ $ 12 = 2,760 @ $ 13 1,040 = During the year, The Shirt Shop sold 730 T-shirts for $18 each. b. Compute the difference in gross margin between the FIFO and LIFO cost flow assumptions. FIFO LIFO Difference Gross margin