The Shirt Shop had the following transactions for T-shirts for Year 1, its first year of operations: Jan. 20 Purchased 550 units @ $ 10 = $ 5,500 Apr. 21 Purchased 350 units @ $ 12 = 4,200 July 25 Purchased 430 units @ $ 15 = 6,450 Sept. 19 Purchased 240 units @ $ 17 = 4,080 During the year, The Shirt Shop sold 1,260 T-shirts for $26 each. c. Compute the difference in gross margin between the FIFO and LIFO cost flow assumptions