Can any one me with american history

explanation:

the addition to geographic boundaries that might have  kept the people of the huang river civilization from traveling to far distance region is that they had learned about the other river valley civilizations but feared contact would bring invasion.

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the presidential debate between carter and reagan in 1980 was ranked among the highest ratings achieved by any television program in the previous decade (the 1970s). carter focused on portraying reagan as a "war hawk" and a "right-wing radical", which could be considered as comments with no factual evidence. however, reagan openly criticized medicare and social security benefits, stating the fact that national debt was approaching $ 1 trillion. these arguments, plus his closing remarks, in which he asked viewers to question themselves "if it is easier for them to buy things in the store or find employment than 4 years ago", were key to him win the election by a vast margin during that year.

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