The following data pertain to Duffy Corporation. What is Duffy's operating profit margin?

Accounts receivable	$ 490,000
Annual sales	$ 4,800,000
Earnings before interest and taxes (EBIT)	$ 350,000
Interest expense	$ 70,000
Net fixed assets	$ 2,400,000
Net income available to common shareholders	$ 168,000
Total assets	$ 4,540,000
Total common equity	$ 2,210,000

3.7%

15.8%

7.2%

7.7%