Contribution margin ratio

a$.$ Coastal Company budgets sales of $$1,280,000,$ fixed costs of $$83,500,$ and variable costs of $$371,200.$ What is the contribution margin ratio for Coastal $\%$

b$.$ If the contribution margin ratio for Bushner Company is $66\%,$ sales were $$904,000,$ and fixed costs were $$423,610,$ what was the operating income?