Compared to the energy of an electron in the second shell of an atom of sulfur, the energy of an electron in the 1.
first shell is lower.
2.
first shell is the same.
3
third shell is lower.
4
third shell is the same.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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5.6⋅10−^19  j

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