Exercise 5-5A Effect of inventory cost flow on ending inventory balance and gross margin The Shirt Shop had the following transactions for T-shirts for 2018, its first year of operations: Jan. 20 Purchased 400 units @ $8 Apr. 21 Purchased 200 units @ $10 July 25 Purchased 280 units @ $13 Sept. 19 Purchased 90 units @ $15 During the year, The Shirt Shop sold 810 T-shirts for $20 each. || || || || $3,200 2,000 3,640 1,350