Springtown Corporation has provided the following contribution format income statement. All questions concern situations that are within the relevant range. Sales (3,000 units) $150,000 Variable expenses 90,000 Contribution margin 60,000 Fixed expenses 48.000 Net operating income $ 12,000 EQUIRED k. What is the margin of safety in dollars? 1. What is the margin of safety percentage? m. What is the degree of operating leverage? n. Using the degree of operating leverage, what is the estimated percent increase in net operating Income of a 15% increase in sales