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.

[Q]: Question: What long molecules are composed of chains of units called monomers? Answer: polymers
[A]: Polymers are long molecules composed of chains of units called monomers.

[Q]: Question: Methyl groups are found within what? Answer: amino acids
[A]:
Methyl groups are found within amino acids.