How does a catalyst work?

rain is the best answer

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation:

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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