Suppose researchers were interested in determining the relationship, if any, between the use of cell phones and the incidence of brain cancer. Would it be better to use a randomized experiment, a case–control study, or an observational study that did not use cases and controls? Explain.

Rachel is studying the population of a particular bird species in a national park. she observes every 10th bird of that species that she can find in the park. her conclusion is that the birds living in the park who belong to that species generally feed on insects. rachel's sample is . based on the sample she picked, rachel's generalization is . reset next