Hi can someone please help me with this!

3)
Experimental group - Those that received the placebo
Control group - Those that received surgery
Dependent variable - Kind of treatment for knee problem
4)
Experimental variable - Use of repellant
Independent variable - Use of repellant
Dependent variable - Deer population around the trees
Control - Trees without the tiger urine
Controlled variables - Specie of the deer, specie of tiger producing the urine.
We can see that in each case, the experiment is trying to establish a cause and effect relationship. This implies, does X lead to Y? Each experiment must have a dependent variable that changes and an independent variable that is manipulated.
3)
Experimental group - Those that received the placebo
Control group - Those that received surgery
Dependent variable - Kind of treatment for knee problem
4)
Experimental variable - Use of repellant
Independent variable - Use of repellant
Dependent variable - Deer population around the trees
Control - Trees without the tiger urine
Controlled variables - Specie of the deer, specie of tiger producing the urine.
Learn more about experiment:https://brainly.com/question/11256472
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