Barnacles live in salt water attached to sturdy objects such as rocks. All the appropriate rock surfaces in a bay are already covered with barnacles. This LACK OF SURFACES to attach to is an example of Climate
Space
Water

particle   p is an electron and particle q is a neutron

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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