Porter Plumbing's stock had a required return of 11. 75% last year, when the risk-free rate was 7. 50% and the market risk premium was 4. 75%. Then an increase in investor risk aversion caused the market risk premium to rise by 2%. The risk-free rate and the firm's beta remain unchanged. What is the company's new required rate of return? (Hint: First calculate the beta, then find the required return. ).