Contribution Margin and Contribution Margin Ratio For a recent year, McDooley's, a family-owned group of restaurants, had the following sales and expenses: Assume that the variable costs consist of food and paper, payroll and employee benefits, and 40% of the selling, general, and administrativ expenses. a. What is McDooley's contribution margin? $ X b. What is McDooley's contribution margin ratio? Round your percentage answer to one decimal place. X% c. How much would operating income increase if the stores sales increased by $7,600 for the coming year, with no change in the contribution margin ratio or fixed costs? $x d. What would have been the operating income or loss for the recent year if sales had been $7,600 more? $x