Mineral composition affects the classification of igneous rock. in simplified classification, igneous to is are classified by the type of feldspar present, by the I type a of feldspar present, or the absence of quartz. in case of neither present, then by the type of iron or magnesium present.
Radon is <span>not a source of air pollution related to human activities</span>
I believe visible light is made from photons
The most water on earth is held by the oceans .
