How much more gas (in gallons) will he get for $20 USD if he buys the gas before crossing the border
instead of buying it in Canada? (1.000 liter = 0.264 US
gallons).

a

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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