please help with A, B, C, and D

The following table summarizes the yields to maturity on several one-year, zero-coupon securities a. What is the price (expressed as a percentage of the face value) of a one-year, zero-coupon corporate bond with a AAA rating? b. What is the credit spread on AAA-rated corporate bonds? c. What is the credit spread on B-rated corporate bonds? d. How does the credit spread change with the bond rating? Why? Data table - - X a Jond with a AAA rating? TH (Click on the following icon in order to copy its contents into a spreadsheet) Important The yields displayed are annually compounded yields Security Yield (%) Treasury 3.09 AAA corporate 320 BBB corporate 4.16 B corporate 4.85 Print Done