Valdez Corporation has provided the following contribution format income statement. Assume that the following information is within the relevant range. Sales (1,000 units) $ 500,000 Variable expenses 200,000 Contribution margin 300,000 Fixed expenses 300,000 Net operating income $ 0 If the company were to sell 20 additional units, by how much would the net operating income increase?

A) $10,000

B) $6,000

C) $60,000

D) cannot be determined with the information given.