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.
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Question: Question: What is the main element in organic compounds? Answer: carbon

Answer: Carbon is the main element in organic compounds. Carbon can form stable bonds with many elements, including itself.

Question: Question: Predators can replace what tool in agriculture. Answer: pesticides

Answer: Predator species such as birds and spiders control insect pests. They reduce the need for chemical pesticides, which are expensive and may be harmful to human beings and other organisms.

Question: Question: What is mass number? Answer: the total number of protons and neutrons in a nucleus

Answer:
All oxygen atoms have eight protons, and most have eight neutrons as well. What is the mass number of an oxygen isotope that has nine neutrons? What is the name of this isotope?.