Markowis Corporation sells three different models of mosquito zapper. Model A12 sells for $52 and has variable costs of $39. Model B22 sells for $109 and has variable costs of $75. Model C124 sells for $407 and has variable costs of $311. The sales mix of the three models is: A12, 55%; B22, 30%; and C124, 15%. What is the weighted-average unit contribution margin?