Explain what it means to be considered a “renewable” energy source, and what it means to be a “non-renewable” energy source.

Resources are characterized as renewable or nonrenewable

- a renewable resource can replenish itself at the rate it is used such as solar energy, wind energy, hydro energy, and tidal energy.

- a nonrenewable resource has a limited supply such as coal, gas, nuclear energy, and fossil fuels.

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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