A researcher wants to see if a protein-enriched diet will enhance the maze-running performance of rats. One group of rats is fed the high-protein diet for the duration of the study; the other group continues to receive ordinary rat chow. In this experiment, the diet fed to the two groups of rats is the variable.

Independent

Explanation:

In most experiments, there is always a:

1. Variable

This is simply regarded as an element, feature, or factor that is subject to change or be altered.

2. Control

This is simply known as the variable in an experiment that always stay the same. It often act as a check.

3. Independent variable

This is simply refered to as that variable in an experiment that is intentionally changed by the researcher to observe and record its effect on the dependent variable.

4. The dependent variable

This is simply know as what is being studied and it is often expected to change when the independent variable is changed.

In every experiment, the Independent Variable is always the one thing you change. That is the cause while the dependent Variable is known as the change that happens because of the independent variable. That is the effect.

the number of senators, and representatives, the state has in congress.