I would appreciate it if all of this can be done in excel

a. A bond has a coupon rate of 10% paid semiannually. The maturity period is 10 years. If your required rate of return is also 8%, what is the fair price of this bond?

b. You bought a bond at the price of $990 with a coupon rate of 6.75% paid semiannually that matures in 20 years. If you keep the bond until maturity, what is the YTM of this bond?