Variable	Fixed	Total	Operating	Contribution
Case	Revenues	Costs	Costs	Costs	Income	Margin Percentage
a.		$400		$900	$1,100
b.	$2,800		$500		$700
c.	$1,200	$700		$1,200
d.	$1,800		$500			50	%

(For entries with a $0 balance, make sure to enter "0" in the appropriate cell. Round the contribution margin percentage to the nearest whole percent.)

		Variable	Fixed	Total	Operating	Contribution
Case	Revenues	Costs	Costs	Costs	Income	Margin Percentage
a.		$400		$900	$1,100		%

Fill in the blanks for each of the following independent cases.