$1.$ Suppose that there are no prepayment and no default, what are the cash flows for Class A$,$ Class B and Class Z bonds? What is the IRR for the issuer? CMO security offering with sequential annual pay tranches

Rules of cash distributions to $A,B$ and $Z$ : interest is paid currently on tranches A and $B,$ but

it is not paid on tranche $Z$ until principal on the other tranches is repaid. For tranche $Z$

interest will be accrued and accumulated into the investment balance. In addition, to ensure

that the maturity of tranche A securities is kept relatively short, the interest accrued to

tranche $Z$ and all current principal and prepayments from the entire mortgage pool will

be allocated to tranche A$,$ and then to tranche B$.$

Questions

Suppose that there are no prepayment and no default, what are the cash flows for

Class A$,$ Class B and Class Z bonds? What is the IRR for the issuer?

Suppose that there are $15\%$ prepayment and no default, what are the cash flows for

Class A$,$ Class B and Class $Z$ bonds? What is the IRR for the issuer?

$2.$ Suppose that there are $15\%$ prepayment and no default, what are the cash flows for Class A$,$ Class B and Class Z bonds? What is the IRR for the issuer?