Wesley's income statement is as follows:

Sales (10,000 units)	$300,000
Less variable costs	(96,000)
Contribution margin	$204,000
Less fixed costs	(24,000)
Net income	$ 180,000

For each additional unit of sales, net operating income will increase by:

Group of answer choices

$ 30

$ 20.4

$18

$ 9.6