Required Information [The following information applies to the questions displayed below.) The Shirt Shop had the following transactions for T-shirts for 2018, its first year of operations: Jan. 20 Purchased Apr. 21 Purchased July 25 Purchased Sept. 19 Purchased 420 units 150 units 230 units 80 units $ 9- - 2 - 3- $3,780 1,500 2,760 1,040 During the year, The Shirt Shop sold 730 T-shirts for $18 each. b. Compute the gross margin using the FIFO cost flow assumption. FIFO ances Gross margin