please answer carefully other wise I will give downvote

4. A 6%, 15year bond has 3 years remaining on a deferred call feature the call premium is equal to one year interest. The bond is currently priced in the market at Ghs 850. What is the issues current yield? 5. A 12%, 20 year bond is currently trading at Ghs 1,250, what is the current yield? And Zack buys a 10% corporate bonds with a current yield of 6%, how much did he pay for the bond