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: Radioisotopes may vary greatly in their rate of decay, decaying faster if their nuclei are more what? Answer: unstable

A: Different radioisotopes may vary greatly in their rate of decay. The more unstable their nuclei are, the faster they decay.
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Q: Question: What makes up the dense outer layer of bones? Answer: compact bone

A: Compact bone makes up the dense outer layer of bones.
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Q: Question: What are decomposers that feed on the organic matter left over from other decomposers? Answer: saprotrophs

A:
Saprotrophs are decomposers that feed on any remaining organic matter that is left after other decomposers do their work. Examples of saprotrophs include fungi and protozoa.
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