assume that abc company uses a perpetual inventory system the company has the same inventors purchase and sales date for the month of march as shown earlierinventorymarch 1200 units400800purchase march10500 units4502250march20400 units4751900march 30300 units5001500sale march15500 unitsmarch25400 unitsthe physical inventory counts on march 31 shown 500 units on handinstructionunder a perpetual inventory system determine the cost of inventory on hand at march 31 and the cost of goods sold for mar