Question

extrusive and intrusive rocks

Answer 1

extrusive igneous rocks are the rocks which have been cooled on the surface of earth
instrusive igneous rocks are formed inside the earth

Answer 2

The magma cools slowly below the surface of the earth, resulting in the formation of large crystals. Such rocks are called intrusive or plutonic rocks. Granite and dolerite are good examples of such rocks.
Magma comes out to the surface and cools down rapidly, resulting in the formation of small crystals. Such rocks are called extrusive or volcano rocks. Basalt and obsidian are good examples of such rocks.