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 1000 units (the relevant range of production is 500 units to 1,500 units): Sales Variable expenses Contribution margin Fixed expenses Net operating income $ 20,000 13,000 7,000 3,780 $ 3,220 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 5. If sales decline to 900 units, what would be the net operating income? Net operating income 6. If the selling price increases by $2 per unit and the sales volume decreases by 100 units, what would be the net operating income? Net operating income Z. If the variable cost per unit increases by $1, spending on advertising increases by $1100, and unit sales increase by 120 units, what would be the net operating income? Net operating income