Question

briefly describe about the formation of coal...

Answer 1

The coal is formed due to decomposition of dead of some animals and some plants.
After their dead they had decomposed into earth and they had purified the when the they into the different earth layers.

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Answer 2

when the plant remains get very deep under the Earth for millions of year their physical quantities and chemical properties get change the graphical action of temperature and pressure that leads to the formation of coal and this process is also called as carbonisation .