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

Total Per Unit

Sales $(7,200$ units$)$ $ $216,000$ $ $30\mathrm{.}00$

Variable expenses $129,60018\mathrm{.}00$

Contribution margin $86,400$ $ $12\mathrm{.}00$

Fixed expenses $55,200$

Net operating income $ $31,200$

Required:

$($Consider each case independently$)$:

What would be the revised net operating income per month if the sales volume increases by $90$ units?

What would be the revised net operating income per month if the sales volume decreases by $90$ units?

What would be the revised net operating income per month if the sales volume is $6,200$ units?