Whirly Corporation$$s contribution format income statement for the most recent month is shown below:

Total Per Unit

Sales $(10,000$ units$)$ $ $350,000$ $ $35\mathrm{.}00$

Variable expenses $200,00020\mathrm{.}00$

Contribution margin $150,000$ $ $15\mathrm{.}00$

Fixed expenses $135,000$

Net operating income $ $15,000$

Required:

$($Consider each case independently$)$:

What would be the revised net operating income per month if the sales volume increases by $100$ units?

What would be the revised net operating income per month if the sales volume decreases by $100$ units?

What would be the revised net operating income per month if the sales volume is $9,000$ units?