What is preserved remains or traces of organisms?
Fossil
Energy source that can be replaced quickly
renewable resource
Water stored underground in rock layers
aquifer
Using water to help crops grow
irrigation
Burning fossil fuels causes this type of pollution
air pollution
This tells the exact age of something
absolute age
Coal, oil, and natural gas are examples of this
fossil fuels
A large supply of stored water used by people
reservoir
Step where large particles settle to the bottom
sedimentation
Law that helps reduce air pollution in the U.S.
Clean air act
This compares which fossil is older or younger without numbers
relative age
Energy sources that are not fossil fuels
alternative energy sources
Air pollution made from smoke and fog
smog
Step where water passes through filters
filtration
One way humans pollute air
car exhaust, factories, burning fuel
A long period of time in Earth’s history
era
Why fossil fuels are nonrenewable
they take millions of years to form.
Layer of gases that protects Earth from harmful rays
ozone layer
Step where germs are killed in water
disinfection
One way to conserve energy
turn off lights, use less electricity, recycle
Scientists use this to determine the age of fossils using decay
half-life
Energy from the heat inside the Earth
geothermal energy
Water found beneath Earth’s surface
groundwater
Put the water cleaning steps in order
coagulation → sedimentation → filtration → disinfection?
Why protecting air is important
It keeps people healthy and protects the environment