15. (1) What is an island arc? a. A large wooden boat that ferries animals from one island chain to another. b. A crescent shaped volcanic mountain chain created by plate tectonic volcanism. C. An anomalous electrical charge. d. None of the above.

All material in the universe that has mass and occupies space is called

Which area of rivers and streams will most likely contain the most sediment? a. the source b. the mouth c. the middle portion d. none of the above

Approximately what percentage of people speak a language other than English in Maine?

A meander is best described as a A. depression for swimming. B. straight streamline into a lake. C. bend or curve in a stream channel. D. pond located streamside.

Why did the map of Eastern Europe change so frequently for so many years? Answer in complete sentences, using proper grammar, and accurate spelling.

When does a protostar become a true star? A) when the star is 1 million years old B) when the central temperature reaches 1 million Kelvin C) when nuclear fusion begins in the core D) when the thermal energy becomes trapped in the center E) when the

Which cultural achievements occured in nothern and southern europe?

When the force on rocks is great enough, they break, producing vibrations called what?

Name two layers below earth's surface in which convection takes place

What are the main arguments for exploiting the amazon rainforest