Acelestial body orbits the sun. it consists of rock and ice. as it passes close to the sun, the body forms a long tail of dust. which body best matches this description?
asteroid
comet
dwarf planet
planet

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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