Fill in the blanks:
True or False:
One word answer:
Match the following columns:
Answer the following questions:
__________ are the wealth of resources buried deep under the surface of the Earth.
__________ is mixed with coal to produce steel.
There are about _________ known minerals in the Earth.
__________ are the wealth of resources buried deep under the surface of the Earth.
_________ is the most important of all the minerals.
