Please answer the following questions with short answers

Please answer the following questions with short answers1-Discuss possible mistakes in the process of bond valuation and suggest a few best practices that could keep those mistakes from occurring.2-Discuss the impact of the 2001 credit downgrade of the U.S. by Standard & Poor’s on the calculation of risk. Do you agree or disagree with this downgrade? Support your position.3-Analyze the ways in which the value of a stock can be determined and determine which is the most challenging to get right, along with additional steps or strategies that could be used to mediate those challenges.