AN explanation on how you got it Please Im confused in average cost

Required Information [The following information applies to the questions displayed below.] Warnerwoods Company uses a perpetual Inventory system. It entered Into the following purchases and sales transactions for March. . Compute gross profit earned by the company for each of the four costing methods. For specific identification, the March 9 sale onsisted of 95 units from beginning Inventory and 225 units from the March 5 purchase; the March 29 sale consisted of 75 units from he March 18 purchase and 115 units from the March 25 purchase. (Round weighted average cost per unit to two declmals and final nswers to nearest whole dollar.)