Answer
a science experiment, the controlled or constant variable is a variable that does not change. For example, in an experiment to test the effect of different lights on plants, other factors that affect plant growth and health, such as soil quality and watering, would need to remain constant. a dependant variable(opposite)would be the properties of the plants themselves, which the scientist is observing in relation to the changing light. These properties might include the plants' color, height and general health of the plant
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