Give me the correct answers please and thanks (I need help from Plato users check my 3 recent I need help for that because school is confusing)

Which of the following items would serve as a primary source for a historian studiying the american civil war

Experiment to investigate effect of medication on levels of stress in males and females. dependant variable?

Karin bought illegal firearms at a gun show. at her trial, she alleged that she had committed this crime because her boyfriend had threatened to harm her and her two daughters if she did not. her lawyer asked the judge to instruct the jury that the prosecution had an obligation to prove beyond a reasonable doubt that karin had acted freely. instead, the judge told the jury that karin had the burden of proving duress by a preponderance of the evidence. who is correct?