You are an investor in common stock, and you currently hold a well-diversified portfolio which has a required return of 12%, a beta of 1.2, and a total value of $9,000. You plan to increase your portfolio by buying 100 shares of AT&E at $10 a share. AT&E has a beta of 1.8. The current T-bill rate is 5%. What will be the required return of your portfolio after you purchase the new stock?

Select one: a. 12.54% b. 16.17% c. 12.35% d. 9.0% e. 10.67%