When either type of study is feasible, an experiment is usually preferred over an observational study. Explain why. Also explain why it is not always possible for researchers to carry out a study in an experimental framework.

Ethnicity is used to distinguish between groups based on cultural elements, but according to the information presented in the lecture (blank) would encompass the details about a person like the shape of his or her features.

Between 1518 and 1548, spanish conquistadores conquered most of the new world, motivated by the a) desire for scientific knowledge. b)  to urge to claim more territory for spain. c) belief that an all-water western route to the orient existed. d) desire to advance national glory, serve god, and seek personal wealth.

Which idea is central to democracy in the united states? everyone has an equal right to consumer goods. people should not compromise to settle differences. the minority has authority over the majority. freedom must be balanced with respect for the law.