<span>Mesozoic Era is the anwser</span>
Hey There!
Here is your answer:
Your answer is that a experiments should be controlled because the experiment could go out of control which could harm or hurt someone.
Also the definition of a controlled experiment is a part of the experiment that's not touched.
Ex: Water is your controlled experiment that's because our not doing anything to the water.
If you need anymore help just ask me!
Hope this helps!
It can impact its physical characteristics
it would be C because kingdom is animalia, phylum is chordata, class is mammalia and order is carnivora and humans and tigers are both carnivors
