Research then analyze the belief in manifest destiny and explain how the concept influenced the development of the frontier

Manifest Destiny was a major influence on how the frontier developed. Manifest Destiny is the doctrine that our land was one that was destined to stretch from sea to shining sea. The reason that this was influential in the frontier's development is that when plans were being made, instead of slowly expanding outwards, the country exploded out living a middle frontier that was neither as developed as California or the East. 

Manifest destiny has to do with the expansion of the west.

The constant presence of diseases or infectious agents within a given geographic area or population group. it may also refer to the usual prevalence of a given disease with such area or group. it includes holoendemic and hyperendemic diseases. a holoendemic disease is one for which a high prevalent level of infection begins early in life and affects most of the child population, leading to a state of equilibrium such that the adult population shows evidence of the disease much less commonly than do children (malaria in many communities is a holoendemic disease). a hyperendemic disease is one that is constantly present at a high incidence and/or prevalence rate and affects all groups equally. so probably family history.