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When hydrogen fuses into helium, about what share of the mass turns into energy?

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  1. About 50%
  2. About 7%
  3. About 0.7%

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References

  1. Astronomy 2e, 16.2 Mass, Energy, and the Theory of Relativity openstax.org/books/astronomy-2e/pages/16-2-mass-energy-and-the-theory-of-relativity Checked 2026-10-10.

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