Not sure how to do this problem

The Last Price and Last Yield columns indicate each bond s price and YTM at the end of trading. EST Spread indicates the bond's spread above the relevant U.S. Treasury benchmark, expressed as a percentage. UST indicates which U.S. Treasury security maturity is the relevant benchmark for each bond. EST Volume shows the number of bonds traded during the day. Notice also that prices are stated relative to a par value of $100. Assume all bonds have the same default premium. Fill in the value of The Blue Co.'s bonds. If you were to calculate the yield on a security with a 10-year U.S. Treasury security, the yield will be equal to 2.17%. Which bond is trading at a premium? Northern Inc. Allied Co. Gadgetron Inc. The Blue Co