Please Help: PreCalc Question: Solve for all general θ solutions: cos2θ = 1/2

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Step-by-step explanation

a) All the undergraduate students is the population of interest under consideration. 129 undergraduates from University of California Berkeley is the sample for this study

b)  To the general population, The results of the study cannot be generalized since the sample wasn’t taken randomly ( sample consists of undergraduates from just one universitiy and not from the universities of other area, state or country),  it is therefore unclear whether they are representative. Thus, the  study  suggests a causal relationship because it was a randomized experiment.