Final answer:
The unit contribution margin is $33 and the contribution margin ratio is 44%.
Step-by-step explanation:
To calculate the unit contribution margin, we subtract the variable costs per unit from the selling price per unit. In this case, the selling price per unit is $75 and the variable costs per unit is $42. Therefore, the unit contribution margin is $75 - $42 = $33.
To calculate the contribution margin ratio, we divide the unit contribution margin by the selling price per unit and multiply by 100. In this case, the unit contribution margin is $33 and the selling price per unit is $75. Therefore, the contribution margin ratio is ($33 / $75) * 100 = 44%.