Why did southern legislatures enact Jim Crow laws after Reconstruction?

Pj conducts an experimental study on the effects of soft music during high stakes science testing. he randomly assigns students at the school. in one condition he does not provide music for testing while in the other group he does provide the music. he administers a pretest at the beginning of the year and a posttest at the end of the year. pj’s design is best described as a: a. static group comparisonb. pretest-posttest control group designc. control-group-time-series designd. nonrandomized control-group pretest-posttest design

Which of these best describes the function of a "super pac"? a)create bi-partisan legislation that can become law b)organization meant to reign-in spending of political candidates during election cycles c)promote the interests of supreme court justices without breaking specific tampering laws d)raise funds through donations from corporations or individuals to support or oppose specific political candidates

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