Can somebody please explain to me how to do this?

Andrew Industries is contemplating issuing a 30- year bond with a coupon rate of 7.06% (annual coupon payments) and a face value of $1,000. Andrew believes it can get a rating of A from Standard & Poor's. However, due to recent financial difficulties at the company, Standard & Poor's is warning that it may downgrade Andrew Industries' bonds to BBB. Yields on A-rated, long-term bonds are currently 6.41%, and yields on BBB-rated bonds are 6.72%. a. What is the price of the bond if Andrew Industries maintains the A rating for the bond issue? b. What will be the price of the bond if it is downgraded