The correct answer is A. silica.
The amount of silica found in the magma determines the viscosity. The higher the silica in magma, the higher the viscosity of a magma. So the correct answer is silica. It is not among the other choices.
Athens, as a city of Greece, is the best city-state in all of ancient Greece.
Athenians can claim this prestigious title because their city had the best literature, best poetry, the best drama schools, and the best schools.
Athens is most famous for their arts and sciences. This is the city where great thinkers were borne and became known throughout the whole world,
Herodotus - father of history - live and wrote in Athens
Socrates - father of philosophy - taught in Athens' marketplace
Hippocrates - father of medicine - practiced in Athens
Phidias - a scultor who created his great works in the Parthenon, located in Athens.
There are many more great thinkers and artists who were borne and lived in Athens.
Because it had good sources of water and created silt which is fine soil for growing crops.
<span>C.A floating pile of oil-soaked logs in the Cuyahoga River caught fire, and the resulting media attention led to the first Earth Day.</span>
True because it caused people to migrate to the u.s if there wasn't a potato famine than they wouldn't have to move.