financial maths. please solve now

9. A GHC5000 callable bond pays interest at ja = 9% and matures at par in 20 years. It may be called at the end of years 10 to 15 (inclusive) for GH45200. Find the price to yield at least ja = 8% until the redemption. 10. A GH1000 bond, redeemable at par on December 1, 1998, pays semianmal coupons at 12 = 9%. The bond is bought on June 1, 1996. Find the purchase price and construct a bond schedule, if the desired yield is 8% compounded semiannually