An investor was afraid that he would become like King Lear in his retirement and beg hospitality from his children, so he purchased grain "tithes." or shares in farm output, for 1.000 pounds. The tithes paid him 100 pounds per year for 30 years. What interest rate did he receive on this investment? 10.44% 6.93% 9.31% 11.55% 8.14%