cheyenne corp uses a perpetual inventory system. on may $7$th they sold $40$ units at $$17$ each. on july $28$th they sold $30$ units at $$22$ each. on june $1$ cheyenne corp sold $20$ units and on august $27$th they sold $30$ more units. the average cost of goods sold in the sale on june $1$st were $$17$ and on the august $27$th sale were $$20$ what would be the cost of goods sold using fifo, lifo, and the average cost?