Unit Total Units Cost Cost $750 March 1 inventory $25 Purchases: March 5 March 10 3,600 2,800 3.600 $10.750 March 15 Goods Available for Sale Sales: March 11 140 March 19 100 240 Using weighted average cost under a periodic inventory system, what is the balance of Ending Inventory (round intermediate and final calculations to the nearest dollar) as at March 31? $2,640. $2,800. $2,600. $2,720