Preparing Contribution format income statement.

Whirly Corporation's most recent income statement is shown below:

Total Per Unit
Sales (10,000 units) $350,000 $35.00
Less variable expenses 200,000 20.00
Contribution margin 150,000 $15.00
Less fixed expenses 135,000
Net operating income $15,000

Required:

Prepare a new contribution format income statement under each of the following conditions (consider each case independently):

1. The sales volume increases by 100 units.
2. The sales volume decreases by 100 units.
3. The sales volume is 9,000 units.