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

Total Per Unit

Sales $(7,900$ units$)$ $ $260,700$ $ $33\mathrm{.}00$

Variable expenses $142,20018\mathrm{.}00$

Contribution margin $118,500$ $ $15\mathrm{.}00$

Fixed expenses $54,100$

Net operating income $ $64,400$

Required:

$($Consider each case independently$)$:

What would be the revised net operating income per month if the sales volume increases by $60$ units?

What would be the revised net operating income per month if the sales volume decreases by $60$ units?

What would be the revised net operating income per month if the sales volume is $6,900$ units?