Explain what air is, where on Earth it occurs, and how it moves to create wind.

Wind is caused by differences of pressure in the Earth's atmosphere. Air from a high pressure area will move towards an area of low pressure. High winds are caused when air moves between areas with large differences in air pressure.

Explanation:

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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