The wavelength of a transverse wave is often measured from (crest to crest, crest to trough)

halogen, any of the six nonmetallic elements that constitute group 17 (group viia) of the periodic table. the halogen elements are fluorine (f), chlorine (cl), bromine (br), iodine (i), astatine (at), and tennessine (ts).

the sun's light combined with the visible wavelenghts form what is called ultraviolet radiation, which are the long waves at the end of a visible light sprectrum.

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bioteacher101

i think the answer is a.keratin is the pigment responsible for skin color.