Earth has a very hospitable temperature and mix of chemicals that have made life abundant here. Most notably, earth is unique in that most of our planet is covered in liquid water, since the temperature allows liquid water to exist for extended periods of time. Besides liquid water and temperature identify the other features of our planet that make it great for sustaining life?

1. Presence of an atmosphere
2. Solid crust
3. Distance from the sun
4. All of the above.

What is the thickness of the Biosphere?

1. 20 km
2. 19 km
3. 15 km
4. 25 km

Name the cycle through which solar energy moves from non-living to living organisms and back.

1. Carbon cycle
2. Nitrogen cycle
3. Nutrition cycle
4. Energy cycle

Name the basic raw material for life.

1. Nitrogen
2. Carbon
3. Oxygen
4. solar energy