Highway driving school charges $560 per student to prepare and administer written and driving tests. Variable costs of $280 per student include trainers' wages, study materials, and gasoline. Annual fixed costs of $92400 include the training facility and the fleet of cars.

1. For each of the following independent situations, calculate the contribution margin per unit and the breakeven point in units by first referring to the original data provided:

a. Breakeven point with no change in information

b. decrease sales price to $400 per student

c. decrease variable costs to $224 per student

d. decrease fixed costs to $81200

2. Compare the impact of changes in the sales price, variable costs, and fixed costs on the contribution margin per unit and the breakeven point in units.