Calculate Costs of Goods Available for Sale, Ending Inventory, Sales, Cost of Goods Sold, and Gross Profit under Periodic FIFO, Periodic LIFO and Periodic Weighted Average Cost using the details below:

July 1 - Beginning inventory (500 units @ $10)

July 13 - Purchase (250 units @ $13)

July 25 - Sold (100 units @ $15)

July 31 - Ending inventory (200 units)