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 $ $40,000$

Variable expenses $26,000$

Contribution margin $14,000$

Fixed expenses $8,680$

Net operating income $ $5,320$

$1.$ What is the contribution margin per unit?

Note: Round your answer to $2$ decimal places.

$2.$ What is the contribution margin ratio?

$3.$ What is the variable expense ratio?

$4.$ If sales increase to $1,001$ units, what would be the increase in net operating income?

Note: Round your answer to $2$ decimal places.

$5.$ If sales decline to $900$ units, what would be the net operating income?

Note: Round "Per Unit" calculations to $2$ decimal places.

$6.$ If the selling price increases by $$2$ per unit and the sales volume decreases by $100$ units, what would be the net operating income?

Note: Round "Per Unit" calculations to $2$ decimal places.

$7.$ If the variable cost per unit increases by $$1,$ spending on advertising increases by $$1,300,$ and unit sales increase by $160$ units, what would be the net operating income?

Note: Round "Per Unit" calculations to $2$ decimal places.

$8.$ What is the break$-$even point in unit sales?

Note: Round intermediate calculations to $2$ decimal places.

$9.$ What is the break$-$even point in dollar sales?

$10.$ How many units must be sold to achieve a target profit of $$8,400?$

Note: Round intermediate calculations to $2$ decimal places.

$11.$ What is the margin of safety in dollars? What is the margin of safety percentage?

$12.$ What is the degree of operating leverage?

Note: Round your answer to $2$ decimal places.

$13.$ Using the degree of operating leverage, what is the estimated percent increase in net operating income that would result from a $5\%$ increase in unit sales?

Note: Round your intermediate calculations and final answer to $2$ decimal places.