for items 7-8: A biology student wanted to study the effect of fertilizer on the growth of pepper plants. he placed four of the same type of pepper plants into separate containers, each containing the same amount of soil. each pot received a different watering solution, containing varying amounts of fertilizers.
The table below shows the average height of the plants by the end of one week.
Plant group | Fertilizer amount (g) |
1 | 0 |
2 | 5 |
3 | 10 |
4 | 20 |
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avg height of plants (cm) |
3.0 |
3.2 |
4.4 |
5.0 |
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7. which of the plant groups is the control group?
A. plant group 1 C.plant group 3
B. plant group 2 D. plant group 4
8.what is the dependent variable in this experiment?
A. amount of soil
B. amount of fertilizer
C. type of tomato plant
D. height of the plants​