The following is Arkadia Corporation's contribution format income statement for last month:

Sales $1,200,000

Less variable expenses 800,000

Contribution margin 400,000

Less fixed expenses 300,000

Net income $100,000

The company has no beginning or ending inventories and produced and sold 20,000 units during the month.

Required: (6*2=12)

c. If sales increase by 100 units, by how much should net income increase?

d. How many units would the company have to sell to attain target profits of $125,000?

e. What is the company's margin of safety in dollars?

f. What is the company's degree of operating leverage?