How would you make a 30% ethanol solution?

You need 30 ml of alcohol and 70 ml of water.

Explanation:

You want to end up with 100ml of liquid, 30% of which is alcohol. 30% of 100ml is 30/100 100 = 30 ml.

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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