Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

Q: Question: What is a solid particle that is indestructible? Answer: atom

A: Atoms are solid particles that are indestructible.
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Q: Question: Viruses were assumed to exist before they were first seen with an electron microscope in which decade? Answer: 1930 ' s

A: Viruses were assumed to exist before they were first seen with an electron microscope in the 1930s. Multiple hypotheses for viral origins have been proposed.
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Q: Question: Melanocytes are located in which layer of the epidermis? Answer: bottom

A:
Melanocytes are located at the bottom of the epidermis.
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