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 $20,000 Variable Expenses_(12.000) Contribution Margin 8,000 Fixed Expenses _(6.000) Net Operating Income $2,000 Answer at least 3 of the questions below... 1. What is the contribution margin per unit? 2. What is the contribution margin ratio? 3. What is the variable expense ratio