Contribution Margin and Contribution Margin Ratio

For a recent year, McDonald's $($MCD$)$ company$-$owned restaurants had the following sales and expenses $($in millions$)$:

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 marging

ratio or fixed costs? Round your answer to the closest million.

$$

million