How to compute Credit Spread on BB bonds? Do you have formular to computed?

831. A BBB-rated corporate bond has a yield to maturity of 8.2%. A US. Treasury security has a yield to maturity of 6.5%. These yields are quoted as APRs with semiannual compounding. Both bonds pa),r semiannual coupons at a rate of 7% and have five years to maturity. a. What is the price {expressed as a percentage of the face value} of the Treasurgr bond? b. What is the price [expressed as a percentage of the face value} of the BBB-rated corporate bond? c. What is the credit spread 9M3 bonds