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 for Reference:

The yields displayed are annually compounded yields.