Sheffield Corporation sells three different models of a mosquito "zapper." Model A12 sells for $53 and has variable costs of $44. Model B22 sells for $106 and has variable costs of $72. Model C124 sells for $408 and has variable costs of $308. The sales mix of the three models is A12, 57%; B22, 28%; and C124, 15%. What is the weighted-average unit contribution margin? (Round answer to 2 decimal places, eg. 15.50.) Weighted-Average Unit Contribution Margin