<em>Answer:</em>
<em>An Atom can turn into both solid and liquid form depending on the temperature of its surroundings </em>
<em>Explanation:</em>
<em>Scientists have discovered a new state of physical matter in which atoms can exist as both solid and liquid simultaneously.
Researchers have found, however, that some elements can, when subjected to extreme conditions, take on the properties of both solid and liquid states.</em>
Happy Holidays! :)

Looking at the information given in the description, the experiment is testing for the effects of the different salts on the growth of the plants.
This means that the type of salt is the independent variable, or the variable being manipulated and tested.
To ensure fair results, some parts of the experiment would need to be kept the same, which is the control. The only answer choice that makes sense in this instance is A. water.
Agriculture
Unsustainable forest management
Overpopulation
Logging
Paper