# of Units 30 Per Unit Cost $25 Total Cost $750 March 1 inventory Purchases: March 5 March 10 March 15 Goods Available for Sale Sales: March 11 March 19 30 35 40 120 1 80 90 320 3,600 2,800 3,600 $10,750 140 100 240 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? $2,800. $2,720