The president has to approve
5 and 6 are characteristic because Mussolini and Hitler were one political dictatorships
Semantics is the study of word meanings.
It is one part of linguistics, other being syntax: the study of sentence structure, phonology and phonetics: the study of sounds, morphology: the study of word structures and pragmatics: the study of actual use of language.
Christopher Columbus is the answer most likely to be correct but, there is an argument for Leaf Erikson