new inventions such as machines
Answer:
Students who take a PE class and who will be eating sugary snacks before PE.
Explanation:
The control variable (or control group) is an experimental element which is constant or unchanged throughout the course of the experiment.
The option "students who take PE class and who will be eating sugary snacks before PE" will remain unchanged and constant because the whole point of the experiment is to see the effects on students performance in PE after eating sugary snacks.
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Answer:
It causes the object to slow down or stop.
Explanation:
Friction is a unknown force pressing against another force slightly, making the moving object slow down.
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