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Warnerwoods Company uses a periodic inventory system. It entered into the following purchases and sales transactions for March. For specific identification, units sold include 80 units from beginning inventory, 375 units from the March 5 purchase, 75 units from the March 18 purchase, and 155 units from the March 25 purchase. Compute gross profit earned by the company for each of the four costing methods. Note: Round your average cost per unit to 2 decimal places and final answers to nearest whole dollar. For specific identification, units sold include 80 units from beginning inventory, 375 units from the March 5 purchase, 75 units from the March 18 purchase, and 155 units from the March 25 purchase. 4. Compute gross profit earned by the company for each of the four costing methods. Note: Round your average cost per unit to 2 decimal places and final answers to nearest whole dollar