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. (Round answers to O decimal places, e.g. 1,250. Use weighted-average unit cost rounded to 3 decimal places for computations.)

But why? for number 3

Zina Manufacturing Company started and completed Job 501 in December with the following Job Cost Sheet and transferred it to the warehouse. Direct Materials Date Dec 17 Dec 30 Total Direct Labor Amount Date Amount $2,000 Dec 20 $4,000 8,000 Dec 30 3,800 Total Job Cost Sheet - Job No. 501 Total Cost The journal entry to record the transaction is A) WIP Inventory FG Inventory B) Cost of Goods Sold WIP Inventory C) FG Inventory WIP Inventory D) FG Inventory WIP Inventory Debit Credit 35,800 17,800 17,800 Manufacturing Overhead Date Amount Dec 24 $10,000 Dec 30 8,000 Total 35,800 35,800 17,800 17,800 35,800