introduction to planet earth

Planet Earth is often referred to as the "blue planet" because of all the water covering Earth. About how much of our planet is covered in water?

• 75% or 3/4

• 25% or 1/4

• 10% or 1/10

• All of earth, 100%

Where is most of Earth's freshwater found?

• Rivers, lakes, and streams

• Underground in groundwater

• Oceans and seas

• Frozen in polar ice caps and glaciers

All the water (solid, liquid, or gas) on Earth is known as which sphere?

• Biosphere

• Hydrosphere

• Atmosphere

• Geosphere

All of the living things on Earth (animals, plants, fungi, protista, and bacteria) are known as Earth's ___________________.

• Hyrdosphere

• Biosphere

• Atmosphere

• Geosphere

All the air that surrounds our planet is known as which sphere?

• Atmosphere

• Biosphere

• Geosphere

• Hydropshere

Earth's rocky surface (land) is known as Earth's _______________________________.

• geosphere

• atmosphere

• biosphere

• hydrosphere

What percentage of Earth's total water is found in its salty seas and oceans?

• 33%

• 75%

• 97%

• 100%

Most of Earth's water is fresh drinking water

• True

• False

What is Earth's outermost layer called? This is the thinnest layer and made of rock.

• Crust

• Mantle

• Outer Core

• Inner Core

The thickest layer of Planet Earth is the ____________________. This layer sits below the crust. The top part of it is liquid rock and the bottom part is solid rock.

• Mantle

• Inner core

• Outer core

• Crust