3 redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. One tree is left outside in normal conditions. The heights of the trees are measured once a week. What is the independent variable? What is the dependent variable? What is the control group?

The correct answer is -

The independent variable - Humidity levels

The dependent variable - Height

The control group - Tree kept outside of the greenhouse

Explanation:

In this study or experiment, the independent variable is the different humidity level as it is what is changed in the study to see its effect on the growth of the redwood tree. The independent variable is manipulated in the experiment to see the change or effect in the dependent variable occurs.

The dependent variable is the variable which \depends on the independent variable as the Independent variable manipulated the dependent variable is measured to the effect which is the height of the redwood trees here.

The control group is a groub of subjects that did not get the treatment that experiment group recieves as it is kept for analysing the deviation from the natural condition. The control group is the redwood trees that are kept in natural environemnt outside of the greenhouse.

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