Given a scientific question, generate a correct answer to it.
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Question: For most of a star's life, hydrogen atoms fuse to form what?

Answer: helium atoms

Question: Which theory describes the benzene molecule and other planar aromatic hydrocarbon molecules as hexagonal rings of sp2-hybridized carbon atoms with the unhybridized p orbital of each carbon atom perpendicular to the plane of the ring?

Answer: valence bond theory

Question: What state of matter exists if particles do not have enough kinetic energy to overcome the force of attraction between them?

Answer:
solid