I don't know what you mean by your question, but if you are making an appropriate title it will be good if you title it that is unique and would want to make your reader more interested with your story. Just trying to help :)
Answer:
<u><em>C.)</em></u> <em>Crest to trough</em>
Answer:True
Explanation:Viruses are a very huge problem these days as they are a 100 times bigger than an actual blood cell or bacteria a virus is just a bunch of bacteria in one big bunch
The Earth Is billions of years old and Earth is much more different now than it was then.
