1. The tennis coach at Kingston High School wants to videotape his varsity
players to evaluate their form when
serving the ball. He is concerned that
the presence of the video recorder
will make some of the players
nervous and affect their service form.
He decides to conduct an experiment
and randomly chooses half of his
players to be videotaped and the
remaining half not to be taped. Then
he will see if having a video camera
on the court affects his players by
noting what percentage of serves by
players in both treatment groups are
successful.
The control variable in his proposed
experiment is the:
Answer choices:
serving percentage.
video recording.
varsity players.
nervousness

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