Exercise $5-1($Algo$)$ The Effect of Changes in Sales Volume on Net Operating Income $[$L$05-1]$

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

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 $7,700$ units?