The organism that was most likely to live at the same time as brachiopods were
Trilobites
<span>Mendel formed a possible explanation for the outcomes he observed in pea plants. Mendel formed a <em>"Hypothesis".</em>
I hope that helped!</span>
A constant in an experiment is <u>B. </u><span><u>the quantity that must remain the same</u>. If it is constant, it doesn't change, so it cannot be variable. D makes no sense.
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