How was coal formed or made, developed ?????????
Kindly refer to the following link:
https://www.meritnation.com/ask-answer/question/how-coal-and-petroleum-was-formed/carbon-and-its-compounds/3103665
https://www.meritnation.com/ask-answer/question/how-coal-and-petroleum-was-formed/carbon-and-its-compounds/3103665