I got 6.17% for 7A and 6.96% for 7B. I need help with the equation to use for 7C. I cannot use excel ot financial calculator

7. An IBM bond has 11 years until maturity, a coupon rate of 8%, a par value of $1,000 and sells for $1,150. a. If coupon payments are made semi-annually, what is the yield to maturity for the bond? b. What is the coupon yield on the bond? c. If you sell it after 1 year and interest rates have increased to 7.5%, what return do you earn