How Big is a Billion? Some people say that the age of the earth should be measured in billions, but that number is hard to comprehend. How much paper would it take to represent a billion? Or to represent the age of the Earth? Let's say 1 page contains 4,000 asterisks. How many pages will show 1,000,000 asterisks? How many pages do you need to show 1 billion asterisks?

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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