Help Needed on Calculating Spot Rates

Hi,

Can some one please explain how to calculate spot rates when ytm rates are given , Conside below example.

The yield to maturity for a benchmark one-year annual-pay bond is 2%, for a benchmark two-year annual-pay bond is 3%, and for a benchmark three-year annual-pay bond is 4%. A three year, 5% coupon, annual-pay bond with the same risk and liquidity as the benchmarks is selling for $102.7751 today (time zero) to yield 4%. Is this value correct for the bond given the current term structure?

I wrote an article on yield curves that may be of some help here: http://financialexamhelp123.com/par-curve-spot-curve-and-forward-curve/