Alana Inc. uses a periodic inventory system. It the following account balances at December 31. Advertising Expense $1,000 Delivery Expense 750 Merchandise Inventory, ending 2.100 Merchandise Inventory, opening 1,500 Purchases 20.000 Purchases Discounts 900 Purchase Returns and Allowances 2,000 Salaries Expense 7,000 Transportation-In 690 Cost of Goods Purchased totals A) $17.100 B) $16.350 C) $17.790 D) $17 190