Carla has a list of 720 students in her middle school, which goes from grade 5 to 8. She wants to survey 40students in the middle school about the upcoming
election. Which of the following would NOT ensure a valid random sample?
O Randomly select 10 names from each grade to survey.
Select every 5th person who enters the cafeteria until 40 students are surveyed.
Pull 40 names out of a hat containing the names of all 720 students and survey them.
Survey 40 eighth graders because they are the oldest and know more about the
election