Ivanhoe Corporation sells three different models of mosquito "zapper." Model A12 sells for $50 and has variable costs of $35. Model B22 sells for $105 and has variable costs of $70. Model C124 sells for $425 and has variable costs of $315. The sales mix of the three models is as follows: A12, 50\%; B22, 15\%; and C124,35\%. (a) Your answer is correct. What is the weighted-average unit contribution margin? (Round answer to 2 decimal places, e.g. 15.25.) Weighted-average unit contribution margin \$ eTextbook and Media Attempts: 1 of 2 used (b) If the company's fixed costs are $358,750, how many units of each model must the company sell in order to break even