15 of 21 This test: 21 point(s) possible This question: 1 point(s) possib Mi Tierra Driving School charges $680 per student to prepare and administer written and driving tests. Variable costs of $408 per student include trainers' wages, study materials, a of $63,920 include the training facility and fleet of cars. Requirement 1. For each of the following independent situations, calculate the contribution margin per unit and the breakeven point in units: Begin by showing the formula for contribution margin per unit and then enter the amounts to calculate the contribution margin per unit for each situation (Abbreviation used CM c CM per unit Situation a Situation b. Situation c. Situation d Now select the labels to show the formula for breakeven point in units and then enter the amounts to calculate the breakeven point in units for each situation (Complete all answer t contribution margin.) ( + Required sales in units Situation a Time Remain