For a recent year, McDonald's (MCD) company-owned restaurants had the following sales and expenses (in millions): Sales $15,200 Food and packaging $(4,288) Payroll (3,800) Occupancy (rent, depreciation, etc.) (4,452) General, selling, and administrative expenses (2,200) $(14,740) Operating income $460 Assume that the variable costs consist of food and packaging, payroll, and 40% of the general, selling, and administrative expenses. a. What is McDonald's contribution margin? Round to the nearest million. (Give answer in millions of dollars.) million $ b. What is McDonald's contribution margin ratio? % c. How much would operating income increase if same-store sales increased by $900 million for the coming year, with no change in the contribution margin ratio or fixed costs? Round your answer to the closest million. $ million