You are trying to compare the interest rate risks of two bonds: (i) a 15-year 8% bond, and (ii) a 10-year 6% bond. Both bonds pay semi-annual interest payments. The current market interest rate for the 15-year bond is 7.2% and the market interest rate for the 10 year old bond is 5.8%

a. determine the (macaulay) durations of the two bonds

b. based on your findings in a and b which bond has a greater interest rate risk? explain.

Please show excel solutions thank you!!