Problem 7-26 Uncle Fred recently died and left $335,000 to his 50-year-old favorite niece. She immediately spent $120,000 on a town home but decided to invest the balance for her retirement at age 65. What rate of return must she earn on her investment over the next 15 years to permit her to withdraw $70,000 at the end of each year through age 80 if her funds earn 8 percent annually during retirement? Use Appendix A and Appendix D to answer the question. Round your answer to the nearest whole number.