B. Chemical energy to start a chemical reaction
The answer is Vestigal. It is a type of anatomical structure that no longer serves any function. Over time they are no longer needed in the body. Apart from the wisdom tooth, another example would be the tail bone which has no use for humans.
I believe that The answer is
The answer to your question is 9.60.
This is actually incorrect, the distance as stated above either from trough to trough or from crest to crest within a corresponding wave, would be referred or called as the wavelength of the given wave.
