Contour Company uses a perpetual inventory system. It entered into the following calendar-year purchases and sales transactions. Date Activities Units Acquired at Cost Units Sold at Retail January 1 Beginning inventory 660 units @ $35 per unit February 10 Purchase 330 units @ $32 per unit March 13 Purchase 110 units @ $20 per unit March 15 Sales 760 units @ $75 per unit August 21 Purchase 180 units @ $40 per unit September 5 Purchase 570 units @ $36 per unit September 1