The following are the information pertaining to inventory for Grace Incorporation for the month ended 31 July 2018. The company uses periodic inventory system. Date July 1 Beginning inventory Description Quantity Unit Cost/ Selling price $15 18 28 28 20 20 32 5 Purchase 8 Sale 10 Sale return 15 Purchase 16 Purchase return 20 Sale 25 Purchase 140 110 10 90 20 REQUIRED: (a) Determine the cost of goods available for sale. (b) For each cost flow assumptions, calculate () the ending inventory, () the cost of goods sold and (ii) gross profit. (1) FIFO (2) LIFO (3) Average cost (c) Which cost flow method results in (1) the highest inventory amount for the balance sheet, Focus and (2) the highest cost of goods sold for the income statement