Answer:
a.- above par (premium)
b.- below par (discount)
Step-by-step explanation:
Currenly the bonds par yield will be of 7.6%
Before the downgrade the expected return on that risk was 7.5% so it was above par.
Once the downgrade occurs: the expected return considering the increased risk is 7.8% Therefore the market price will decrease. This will move the yield to maturity from 7.5% to 7.8% and the market price below par.