A useful material that can be drawn from when needed is called a _____

• a resource
• a problem
• a solution
• conservation

A challenge or situation that needs to be solved is called a _____

• a resource
• a problem
• a solution
• conservation

A means of dealing with a difficult situation is called a _____

• a resource
• a problem
• a solution
• conservation

What is the name of the  long channels, built by the Romans, to carry water to cities?

• pipelines
• waterways
• conduits
• aqueducts

Which river flows through the city of Rome?

• the Po River
• the Tigris River
• the Tiber River
• the Euphrates River

Why was water from the Tiber River undrinkable by the Romans?

• it was salty
• it was far from the city
• it was polluted
• it was scarce

The factories in Israel that remove the salt from the saltwater are called _____

• Mediterranean movers
• desalination plants
• salt shakers
• water recyclers

In most cases, the process of getting the salt and other impurities out of the water _____

• is inexpensive
• requires little energy
• is extremely practical
• is not very practical

Humans go through freshwater quickly by turning it mostly into _____

• urine and saliva
• saliva and sweat
• blood, sweat and tears
• urine and sweat

What percentage of the water used by astronauts is recovered?

• 39 %
• 63 %
• 93  %
• 99 %