Answer Happy

Does coaching raise SAT scores? Because many students score higher on a second try even without coaching, a study looked at a simple random sample of 4.000 students who took the SAT twice. Of these, 500 had taken coaching courses between their two attempts at the SAT. The study compared the average increase in scores for students who were coached with the average increase for students who were not coached. This study compares two groups, but it is not an experiment because: there is no response variable. Othere is no explantory variable. O each student chose whether or not to take a coaching course. O random selection was used to produce the data.