Sales $(8,000$ units$)$$ $272,000$$ $34\mathrm{.}00$Variable expenses$152,00019\mathrm{.}00$Contribution margin$120,000$$ $15\mathrm{.}00$Fixed expenses$54,100$Net operating income$ $65,900$

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 $7,000$ units?