plz Answer this ASAP

Q3 Serena Inc. is a retailer operating in Germany. Company uses the perpetual inventory method. All sales returns from customers result in the goods being returned to inventory; the inventory is not damaged. Assume that there are no credit transactions, all amounts are settled in cash. You are provided with the following information for Serena Inc. for the month of January 2020. Date Description Quantity Selling Price January 1 January 5 January 8 January 10 January 15 January 16 January 20 January 25 Beginning inventory Purchase 1 Sale Sale return Purchase Purchase return Sale Purchase 120 140 110 15 55 05 90 30 $15 18 28 28 20 20 32 22 Instructions: (a) For each of the following cost flow assumptions, calculate (i) Cost of goods sold (ii) Ending inventory (iii) Gross profit By using (1) LIFO (2) FIFO and (3) Moving-average cost, and Compare results for the three cost flow assumptions