Joseph sets up an experiment growing corn in three containers. Each container has the same amount of
potting soil and fertilizer. Each corn plant is five centimeters (cm) tall. The containers are all placed so thatthey
receive the same amount of light. All of the plants are grown at the same temperature. The plants are
watered once a week: container #1 receives 10 ml of water, container #2 receives 20 ml of water, and
container #3 receives 30 ml of water. Joseph measures the growth of each plant for six weeks.
Which hypothesis is being tested?
The amount of water supplied will affect plant growth.
The temperature will affect plant growth.
The type of fertilizer will affect plant growth.
The amount of light exposure will affect plant growth.

Because that is the only variable being altered or changed, every other variable remains consistent. In any experiment what your testing is what's altered between each subject or test group.

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