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Biology, 14.07.2019 21:50 merunikitty1226

Johannes wants to know whether soil, water, or both are needed for plant growth. he chooses to conduct experiments on a willow tree for five years to answer his question. how can his experimental methods be changed to improve his experiment? he needs to ask scientists what they think. he needs to conduct the experiment for a longer period. he needs to use a larger sample size. he needs to test more factors in the environment.

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Johannes wants to know whether soil, water, or both are needed for plant growth. he chooses to condu...
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