Question

How was coal formed?

Answer 1

coal is formed by the degradation of plants and animals under the surface of the earth

Answer 2

About 300 million years ago, there were dense forests in low lying wetland areas on earth. As the trees died, they got covered with sand and mud. More trees died and got covered up. This process went on for centuries. The high temperature and high pressure in side the earth converted the buried vegetation into coal

This is the way coal was form.