Help with Q1-4-5 please. Thank you

1. What is a mortgage pay-through bond (MPTB)? How does it resemble a mortgage-backed bond (MBB)? How does it differ? 2. Are the overcollateralization requirements for mortgage pay-through bonds the same as for mortgage-backed bonds? 3. Name two different ways that MPTBs can be overcollateralized. 4. What is a CMO? Explain why a CMO has been called as much of a marketing innovation as a financial innovation. 5. What is meant by a derivative investment