Adout how long ago did humans arrive in the americans

no statements but ok.

the statement that best describes the idea of manifest destiny that was used in the 19th century would be that "it was fate that the united states would continue to  expand westward," since people thought the us was "destined" to do so. 

social contract theory, nearly as old as philosophy itself, is the view that persons' moral and/or political obligations are dependent upon a contract or agreement among them to form the society in which they live

i would say it is the roman empire europe after the norman conquest.