These are types of high energy These are visible dark spots on article outflows occurring in the surface of the Sun caused
the Sun's photosphere. by intense magnetic activity
forming areas of reduced
surface temperature.
This is the visible surface of the
sun which is about 100 km
thick and composed of gas; it is
the region of the sun that
produces visible light
Photosphere
Corona
Sunspots
Prominence and Solar
ding moddion where

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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