Which two particles are found in the nucleus of an atom?

Neutrons and Protons are found in the nucleus of an atom. Electrons circle around the atom. So the answer is Neutrons, and Protons.

where's the diagram?

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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