10) Contrast positive feedback mechanisms and negative feedback mechanisms.
11) Soil is an example of an interface in the Earth system. What is a interface? With which of Earth's four spheres is soil associated?
12) What are two sources of energy for the Earth system?
13) Briefly describe the events that led to the formation of the solar system.
14) List and briefly describe Earth's compositional divisons.
15) Contrast the asthenosphere and the lithosphere.