Please explain

Spring Company had the following inventory information in 2018 #of units Unit costTotal cost Jan. 1 Beginning inventory April 1 Purchase July 1 Purchase 250 units 600 units 150 units $10 15 20 $ 2,500 9,000 3,000 $14,500 1,000 In 2018, Spring sold 800 units for $40 each. Using the average cost method, determine the 2018 gross profit