how to solve

Multiple Choice 3 points I wish to investigate if middle school students who receive peer tutoring in the county actually score better in their math classes. Instead of looking at every middle school student in the county, I choose to take a random sample of all middle school students taking Geometry and a random sample of all middle school students taking Algebra. For each of those groups, I record their math grade before tutoring began and again at the end of the year. Which type of sample did I use? convenience representative systematic cluster stratified Oo simple random