P. Lange Inc. hired your consulting firm to help them estimate the cost of equity. The yield on Lange's bonds is 7.25%, and your firm's economists believe that the cost of equity can be estimated using a risk premium of 3.50% over a firm's own cost of debt. What is an estimate of Lange's cost of equity from retained earnings?

a. 10.75%

b. 11.18%

c. 11.63%

d. 12.09%

e. 12.58%