Suppose that you want to test the effects of different dishwashing detergents on dishes that have food stuck to them. to test the differences, you wash three loads of the same dishes, each with a different type of detergent, all in warm water. you also wash a fourth load of dishes with only warm water.

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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