Can someone please explain step-by-step if possible?

Miller Companys contribution format income statement for the most recent month is shown below: Total Per Unit Sales (37,000 units) $ 222,000 $ 6.00

Variable expenses 111,000 3.00

Contribution margin 111,000 $ 3.00

Fixed expenses 44,000 Net operating income $ 67,000

Required: (Consider each case independently):

1. What is the revised net operating income if unit sales increase by 20%?

2. What is the revised net operating income if the selling price decreases by $1.30 per unit and the number of units sold increases by 17%?

3. What is the revised net operating income if the selling price increases by $1.30 per unit, fixed expenses increase by $7,000, and the number of units sold decreases by 7%?

4. What is the revised net operating income if the selling price per unit increases by 20%, variable expenses increase by 20 cents per unit, and the number of units sold decreases by 7%?