Question

When the material A mined from the earth is heated strongly in an insufficeint supply of air, it produces a solid fuel B which consists mainly of carbon. When another material C obtained from trees is heated in an insufficient supply of air, it produces another solid fuel D which also consists mainly of carbon. Name A, B, C and D.

Answer 1

A is coal as it is mined from inside the Earth.
B is coke as the burning of coal in insufficient supply of air produces coke.
C is wood as wood is obtained directly from trees.
D is charcoal which is obtained from burning of wood in insufficent supply of oxygen.