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Answer:
the fixed amount of energy that a system described by quantum mechanics, such as a molecule, atom, electron, or nucleus, can have.
Explanation:
Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the steps of a staircase.
Dear Dad,
When are you bringing the milk back from the store, its been twenty two years?
Love,
Son
Answer:
its the 3rd one and the 4th one hope this helps u
