Mortgage markets have developed significantly since the early 1970s through the creation of secondary market instruments in the form of mortgage pass-throughs, collateralized mortgage obligations (CMOs), and REMICs.These collections have been generally referred to as mortgage-backed securities (MBS).In many ways, these instruments carry the characteristics of their underlying assets -- individual mortgages. Mortgages generally carry a no-cost prepayment option. List 6 factors that affect the prepayment speeds on mortgage-backed securities and that the prepayment option depends upon and why?