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Required information [The following information applies to the questions displayed below.] Warnerwoods Company uses a perpetual inventory system. It entered into the following purchases and sales transactions for March. 4. Compute gross profit earned by the company for each of the four costing methods. For specific identification, the March 9 sale consisted of 80 units from beginning inventory and 340 units from the March 5 purchase; the March 29 sale consisted of 40 units from the March 18 purchase and 120 units from the March 25 purchase. Note: Round weighted average cost per unit to 2 decimal places