Bloomington Corporation reported the following on their contribution format income statement:

Sales (12,000 units)

$175,000

Less: Variable expenses

100,000

Contribution margin

75,000

Less: Fixed expenses

62,500

Net operating income

$ 12,500

If sales increase by 10%, net operating income will increase by what amount?

A.$ 1,500

B.$30,000

C.$ -0-

D.$ 7,500