Fragile Inc.'s bonds currently sell for $600 in the market and have a par value of $1,000. The annual coupon rate is 8.75%, paid annually, and the bonds have a 15 -year maturity. What is their yield to maturity (i.e., the market required rate of return)? 3.12% 4.25% 5.51% 6.67% 9.26% 11.04% 13.19% 15.89%