The net income of a company for the year was $570,000. The company has no preferred stock. Common stockholders' equity was $1,800,000 at the beginning of the year and $2,600,000 at the end of the year. Calculate the rate of return on common stockholders' equity. (Round your answer to two decimal places.)

a) 17.98%

b) 25.91%

c) 21.92%

d) 31.67%