can some show me how to arrive at answer?

FIFO            $42,100

LIFO            $56,500

Average     $48,475

  (a) Determine the cost of goods available for sale.(b) Determine (1) the ending inventory and (2) the cost of goods sold under each of the assumed cost flow methods (FIFO, LIFO, and average-cost). Prove the accuracy of the cost of goods sold under the FIFO and LIFO methods. (Note: For average-cost, round cost per unit to three decimal places.)

(c) Which cost flow method results in (1) the highest inventory amount for the balance sheet and (2) the highest cost of goods sold for the income statement?