Answer:
any of two or more forms of a chemical element, having the same number of protons in the nucleus, or the same atomic number, but having different numbers of neutrons in the nucleus, or different atomic weights. There are 275 isotopes of the 81 stable elements, in addition to over 800 radioactive isotopes, and every element has known isotopic forms. Isotopes of a single element possess almost identical properties.
Explanation:
Her conclusion is invalid because using sand instead of soil slows down plant growth. Fertilizer, on its own, does not 'greatly' increase the size of the plant.
The correct way to do this experiment would be to keep all other parameters same, except the fertilizer. This will give her accurate results.
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<span>Mary’s body is unable to use insulin properly. </span>