Required information (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 Variable expenses Contribution margin Fixed expenses Net operating income $ 80,000 52,000 28,000 21,840 $ 6,160 4. If sales increase to 1,001 units, what would be the increase in net operating income? (Round your answer to 2 decimal places.) Increase in net operating income