Chuck has been told that if he invests $500,000 on a solar system he can save $130,000 a year. The lifespan of the panels he is being sold are 10 years at which time they are rendered useless. The required rate of return is 10%. Ignore any tax and assume all cash flows occur at year end except for the initial investment amounts. Calculate the internal rate of return using the interpolation method. Round all results in each calculation to the thousandths. a. 19.892% b. 22.640% c. 10.271% d. 10.190%