The 50s were marked by what

The 1950s were a decade marked by the post-World War II boom, the dawn of the Cold War and the Civil Rights movement in the United States. ... For example, the nascent civil rights movement and the crusade against communism at home and abroad exposed the underlying divisions in American society.

Explanation:

1st and 3rd : ) now lemme smash

- "the past is made of multitudinous items ranging from anything that can be collected, recollected or assessed to originate in the past. as such, the past is a gallimaufry of particulars that may not have been related in any way. however, the human mind seeks organization to understand concepts and other things. the human mind therefore seeks relationships in explaining and studying the past. history being a humanity, dictates that historians have to serve this human trait by bringing structure to details of the past. historians do this by creating interpretive frameworks that capture as many details as possible."

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