Answer :
Final answer:
The independent variable is the number of hours spent studying, while the dependent variable is student test scores. Various other variables such as prior knowledge, test difficulty, and study environment need to be controlled in this experiment.
Explanation:
The independent variable in the experiment conducted by Stephen and Charlie is the number of hours spent studying. This is the factor that is being changed or manipulated.
The dependent variable is the student test scores. It is the outcome that is expected to change based on the variation in the independent variable.
Variables that need to be controlled in this experiment include factors like students' prior knowledge, test difficulty level, study environment, study techniques, and individual differences among students.
Learn more about variables in experiments here:
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