If sales are $20,000, variable costs are $8,000, and fixed costs are $2,000, the contribution margin ratio is: (rounded to the nearest number) O a. 10% O b. None of the given answers O c. 40% O d. 50% O. 60% Mazoon Company has fixed costs of $10,000 and a breakeven point of 400 units. If the company plans to produce 800 units, and sales increase by 10%, its operating income will increase by: O a. None of the given answers O b. 10% e c. 20% d. 60% 30%