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.

99 points which of the following selections is least useful for supporting the claim that states intentionally built unequal school systems to separate the races? question 1 options: a. the supreme court ruling in plessy v. ferguson (1896) declared segregation of schools to be unconstitutional. b. it was very clear by the mid-1900s that southern states had expertly built separate educational systems. these schools, however, were never equal. c. states with laws keeping schools segregated never gave equal amounts of money t o their black and white schools. d. ten years after brown, fewer than 10 percent of southern public schools had integrated. some areas did not comply at all.