How many years does it take for one rock to transform into another rock?

Relatively steep zone that is compared with the shelf that marks the boundary between continental crust and ocean crust.

Computer models can scientists predict weather. some computer models can show the predicted path of hurricanes. what other events could a computer model warn us of? a) undersea earthquakes , tornadoes, and avalanches b) tornadoes c) avalanches d) undersea earthquakes

What is a small water source like a stream or brook?