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

Total Per Unit

Sales $(7,700$ units$)$ $ $261,800$ $ $34\mathrm{.}00$

Variable expenses $146,30019\mathrm{.}00$

Contribution margin $115,500$ $ $15\mathrm{.}00$

Fixed expenses $55,600$

Net operating income $ $59,900$

Required:

$($Consider each case independently$)$:

$1.$ What would be the revised net operating income per month if the sales volume increases by $90$ units?

$2.$ What would be the revised net operating income per month if the sales volume decreases by $90$ units?

$3.$ What would be the revised net operating income per month if the sales volume is $6,700$ units?