Without this material on earth, disposal of bodily wastes and dissolution of minerals would be impossible.

• Gases

• Water

• Land

• Ions

The earth is located in this specific area of space which is "not too hot and not too cold".

• Goldberry' Zone

• Goldilock's Zone

• Goldberg's Zone

• Geothermal Zone

These gases trap the heat from the sun which increases the temperature of earth.

• Oxygen

• Nitrogen

• Carbon Monoxide

• Carbon Dioxide

Approximately how many percent of earth's atmosphere is composed of oxygen?

• 20%

• 21%

• 22%

• 23%

The layer of the atmosphere where the ozone layer is located.

• Troposphere

• Stratosphere

• Mesophere

• Exosphere

Auroras are one of the most beautiful phenomena on earth. On which layer of the atmosphere can it be found?

• Ionosphere

• Mesophere

• Stratosphere

• Thermosphere

The liquid component of the earth.

• Hygrosphere

• Geosphere

• Hydrosphere

• Asthenosphere

The term used to refer to "mountain building".

• Orogenesis

• Oreogenesis

• Oreganogenesis

• Origamigenesis

The concept of ecology is mainly under what subsystem of earth?

• Atmosphere

• Hydrosphere

• Geosphere

• Biosphere

Which of the following is not a biotic factor?

• Air

• Leaves

• Animals

• Humans