Student 2 is right.
<h3>Constant variables</h3>
In research investigations, some variables should be kept constant across various experimental groups in order for the outcome of the investigation to be valid.
For example, in order to test how flatworms respond to different environments, one variable that should be kept constant is the flatworms. The flatworms to be used must be of the same species, sex, age, etc.
The investigator can then go ahead to divide the flatworms into two or more groups and then subject them to different environments. Other variables should also be kept constant in order to determine the effects that are only specific to the different environments only.
More on constant variables can be found here: brainly.com/question/474060
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Im guessing c=solubilty because
Hello there,
<span>The Northeast’s rocky and jagged shoreline provides many habitats.
Hope this helps you.
Have a great day! (:
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To have an overall positive or negative charge. (as opposed to neutral one)
