Required information Skip to question [The following information applies to the questions displayed below.] Oslo Company prepared the following contribution format income statement based on a sales volume of 1,000 units (the relevant range of production is 500 units to 1,500 units): Sales $ 50,000 Variable expenses 27,500 Contribution margin 22,500 Fixed expenses 14,850 Net operating income $ 7,650

13. Using the degree of operating leverage, what is the estimated percent increase in net operating income that would result from a 5% increase in unit sales?