How long does it usually take for a rock to undergo a stage within the rock cycle?

The point where two air masses meet is called a

Which statement best explains distribution of natural resources? people tend to settle in locations that have the resources they need for survival. some countries have resources that others lack, so trade between countries becomes vital. fossil fuels come from areas that have mountains and other areas that manufacture synthetic gas. areas with natural resources provide a higher standard of living and better quality of life.

What is an additional type of erosion found at the coast? what does it mean?