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 20 , 300 Variable expenses 12, 100 Contribution margin 8, 200 Fixed expenses 6, 232 Net operating income 1 , 968 Required: Using the degree of operating leverage, what is the estimated percent increase in net operating income of a 4% increase in sales? (Do not round intermediate calculations. Round your answer to 2 decimal places.) Percent increase in net operating incomet