1. A valuable mineral deposit is located just below the surface of the ground. Which method would be used to obtain the mineral?____________________________
Strip mining

2. The area of land that supplies water to a river system is called a(n)____________________________
watershed

3. Using land to grow food crops is an example of____________________________.
agriculture

4. What is eutrophication?
Over many years, the levels of nutrients in a lake build up in this process.

5. Desertification, urbanization, deforestation
This is an example of how human activities may harm the balance in an ecosystem?
Desertification, urbanization, deforestation

6. Chlorofluorocarbons CFC’S
.Which indoor air pollutant is a colorless, odorless gas that forms when wood, coal, oil, or gas are incompletely burned?
Chlorofluorocarbons
CFC’S

7. One of the acids in acid rain forms when water combines with________.
NITROGEN OR SULPHUR OXIDES

8. What is a major role of technology in controlling air pollution?
Reducing emissions

9. A well in which groundwater rises because of pressure is called a(n)_____.
Artesian well

10. The process of restoring an area of land to a more natural, productive state is called ______________________  
Land reclamation

11. . The water in ponds and lakes is
still

12. A river system is made up of a river and its____.
tributaries

13. Water moves easily through __________materials.
permeable

14. People can obtain groundwater by drilling a well _________.
Into an aquifer

15. Underground layer of rock or sediment that holds water.
An aquifer is a(n)
Underground layer of rock or sediment that holds water.

16. The streams and small rivers that feed into a main river are called
tributaries

17. The type of molecule that is the major cause of the ozone hole and blocks the ozone cycle is called____.
chlorofluorocarbons

18. Farmers may leave fields unplanted or plant alternate crops to reduce
Nutrient depletion

19. Temperature inversion
A(n) _____ is a dangerous weather condition in which a layer of warm air traps smog close to Earth's surface.
Temperature inversion

20. Many uses of land, including logging, mining, and farming, expose the soil, which can lead to_______.
erosion

21. The small lake that forms when a loop of a river is cut off from the main channel is called a(n) _______.
Oxbow lake

22. People may not have enough water during a(n) ___________________, a period when rainfall is below normal.  
drought

23. Building a highway is an example of the type of land use known as ____________________.  
development

24. .Scientists think deforestation is one cause of ______, because carbon dioxide increases when people burn trees to clear land.
Global warming

25. A radioactive gas that is naturally formed by certain types of rocks underground is called _________.
radon

26. A river and all of its tributaries make up a(n) ___________.
River system

27. The main chemical in photochemical smog is _____, which forms when sunlight reacts with certain gases.    
ozone

28. The top of the saturated zone is called the _____.
Water table

29. The area of soil in which the pores are totally filled with water is called the _______ zone.
saturated

30. People cannot use most of the freshwater on Earth because it is in the form of ___________.
ice