2 questions regrading to dollar roll

1)Discuss the risks of roll vs. hold from the perspective of the investor?Why does the dollar roll market exist?

2)Why does the dollar roll market exist? Explain this using all participants in both the primary and secondary markets, from the prospective mortgagor to the dealer and investor in the secondary market.

please do not copy it from chegg or course hero. i posted these two questions and did all my research. thank you.

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