To keep on living, all living things need _____

• Crash Course videos
• YouTube videos of cats
• some form of water
• Marvel superhero movies

How much of the surface of the Earth is covered in water?

• less than half
• about half
• about two-thirds
• more than two-thirds

We actually have enough water on Earth to leave a faucet running for _____

• 136 thousand years
• 136 million years
• 136 billion years
• 136 trillion years

Most of the water on earth is _____

• in flowing rivers
• in large lakes
• trapped in glaciers
• in the oceans

What kind of water is found in rivers, ponds, wetlands, and streams?

• salt water
• fresh water
• hard water
• mineral water

Freshwater contains _____

• less than 0.1% salt
• about 0.1% salt
• about 1% salt
• more than 1% salt

Which field of science deals with the Earth's surface?

• biology
• astronomy
• geography
• archaeology

On a map of the Earth, most of the blue stuff represents _____

• glaciers
• land
• fresh water
• salt water

What percent of the water on the planet is salty?

• less than 95%
• about 95%
• about 97%
• more than 97%

What percent of the planet's total water supply is freshwater?

• less than 3%
• about 3%
• about 5%
• more than 5%