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): Explain how changes in activity affect contribution margin and net operating income. Show the effects on net operating income of changes in variable costs, fixed costs, selling price, and volume. Use the contribution margin ratio (CM ratio) to compute changes in contribution margin and net operating income resulting from changes in sales volume. What is the break-even point in unit sales