Southwest Aniline Inc. uses a periodic inventory system. Its records show the following for the month of May, in which 900 units were sold for a total of $36,000 cash: Number of Date Cost per unit Total cost units May 1 Inventory, beginning 200 $10.25 $2,050 May 10 Purchase 400 $10.50 $4,200 May 25 Purchase 400 $10.75 $4,300 Total 1,000 $10,550 Compute gross profit for the month of May assuming that Southwest Aniline Inc uses the average costing inventory method