When does a high pressure system form? a) when an air mass cools over a cold surface and sinks b) when an air mass cools over a hot surface and rises c) when a cold air mass cools over a cool surface and rises d) when a cold air mass warms up over a hot surface and rises

What benefits does this type of farming have?

17. the soil erosion pictured here is the result of what? a. harvesting renewable resources at a rate greater than the sustainable yield b. a mudslide caused by excessive rains c. harvesting renewable resources at a rate lower than the sustainable yield d. the transition between geologic eras and eons

The process by which liquid water changes into water vapour is called what ?