What were the new river systems and mountain ranges that were added to the U.S.A?

Question

i have to do a s.s project about the expansion of the american west and one of the question that i have to answer is what were the new river systems and mountain ranges that were added to the U.S.A?, i already tried to look it up but i keep getting the wrong answer, so if you know the answer can you plz help me and tell me the answer.

if your just going to say something stupid or tell me go do it myself, then don't bother answering this question

Answer 1

Find a map.  Look at everything west of the Mississippi River.  Find any river west of there and any mountain range west of there and you have your answer.   If you don't have one at home, go to the library.  If not there try Google Earth or Yahoo maps.  It will be difficult to get the wrong answer if you follow my advice.