Restate the following income statement for a retailer in contribution format. $ 91,000 52,780 38,220 Sales revenue ($100 per unit) Less cost of goods sold ($58 per unit) Gross margin Less operating costs: Commissions expense ($7 per unit) $ 6,370 Salaries expense 7,800 Advertising expense 5,900 Shipping expense ($2 per unit) 1,820 Operating income 21,890 $ 16,330 Per Unit Sales Revenue Variable Expenses Commissions Expenses Shipping Expenses Salaries Expenses Total Variable Expenses X DO Cost of Goods Sold Fixed Expenses Contribution Margin Total Fixed Expenses DO Contribution Margin