Keys Industries has assets of $2,100, sales of $2,960, operating costs of $2,675, and $250 of total current liabilities consisting of $200 of accruals and $50 of notes payable. Its long-term debt is $850, its common equity is $1,000, its interest charges are $125, and its tax rate is 40%. What is Keys' profit margin? a. 2.92% b. 2.62% c. 3.56% d. 3.24% e. 2.36%