Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Bacteria are responsible for many types of diseases in humans. Answer: diseases

A: Bacteria are responsible for many types of what in humans?
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Q: Passage: Producers are living things that use energy to make food. Producers make food for themselves and other living things. There are two types of producers:. Answer: producers

A: Living things that use energy to make food, both for themselves and other living things, are what part of an ecosystem?
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Q: Passage: Ionic and covalent compounds are held together by electrostatic attractions between oppositely charged particles. Describe the differences in the nature of the attractions in ionic and covalent compounds. Which class of compounds contains pairs of electrons shared between bonded atoms?. Answer: electrostatic attractions

A:
What holds ionic and covalent compounds together?
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