If you double the lenght of a wire, how does the resistance of the wire change? and

If you make a wire twice as thick, how does the resistance of the wire change?

If the length of a wire is doubled the resistance is shortened if it is thicker is is more durable due to the electrons having more room to spread out and flow through the wire

I hope this will help you

the answer is minerals.

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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