Energy the connection to everything.
Energy cannot be created or destroyed; it can only change forms (like chemical to heat) or be transferred, as stated by the fundamental Law of Conservation of Energy, though the total energy of the universe is complex, with expansion potentially affecting it, and matter and energy are interconvertible (\(E=mc^{2}\)).
The "3 energy levels" refer to the electron shells in an atom, where the third level (n=3) is farther from the nucleus than the first two, containing more complex sublevels (s, p, and d) and holding up to 18 electrons, following rules where lower levels fill first (2 in Level 1, 8 in Level 2, then starting Level 3), defining how electrons occupy space around the nucleus
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