What option can I choose? I know CM ratio= CM/Sales revenue but there is no option like this

Big Foot produces sports socks. The company has fixed expenses of $110,000 and variable expenses of $1.10 per package. Each package sells for $2.20 Read the requirements Requirement 1. Compute the contribution margin per package and the contribution margin ratio Begin by identifying the formula to compute the contribution margin per package. Then compute the contribution margin per package. (Enter the amount to the nearest cent.) Sales price per unit Variable cost per unit Contribution margin per unit The contribution margin per package is S 1.10 Compute the contribution margin ratio. (Enter the ratio as a whole percent.) Begin by identifying the formula to compute the contribution margin ratio. Contribution margin ratio Contribution margin per unit Contribution margin ratio Fixed costs Operating income Sales price per unit Total variable cost Variable cost per unit