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Marlow Company uses a perpetual inventory system. It entered into the following calendar-year 2011 purchases and sales transactions. Units Sold at Retail Activities Beginning inventory Purchase Purchase Sales Purchase Purchase Sales Units Acquired at Cost 720 units @ $46.40/unit 320 units @ $42.40/unit 160 units @ $22.40/unit Date Jan. 1 Feb. 10 Mar. 13 Mar. 15 Aug. 21 Sept. 5 Sept. 10 580 units @ $77.40/unit 280 units @ $62.40/unit 220 units @ $50.40/unit 140 units @ $77.40/unit Totals 1,700 units 720 units Required: 1. Compute cost of goods available for sale and the number of units available for sale. (Omit the "$" sign in your response.) $ Cost of goods available for sale Number of units available for sale units 2. Compute the number of units in ending inventory. Ending inventory units 3. Compute the cost assigned to ending inventory using (a) FIFO, (6) specific identification-units sold consist of 560 units from beginning inventory and 160 units from the March 13 purchase, and (c) weighted average cost. (Due to rounding, the sum of Cost of Goods Sold and Ending inventory may not equal the Cost of Good available for sales. Round your per unit costs to 2 decimal places. Round your final answers to the nearest dollar amount. Omit the "$" sign in your response.) Ending inventory $ (a) FIFO (b) Specific identification $ (c) Weighted average cost $ 4. Compute gross profit earned by the company for each of the three costing methods. (Round your per unit costs to 2 decimal places and inventory balances and final answer to the nearest dollar amount.Omit the "$" sign in your response.) Gross profit $ (a) FIFO (b) Specific identification $ (c) Weighted average cost $