A geyser is the result of underground water under the combined conditions of high temperatures and increased pressure beneath the surface of the each. Since temperatue rises approximately one degree F for every sixty feet under the earth’s surface, and pressure increases with depth, water that seeps down in crachs and fissures until it reaches very hot rocks in the earth’s interior becomes heated to a temperatue in excess of 290 degrees F. Because of the gressure, it shoots out of the surface in the form of steam and hot water. The result is a geyser.For the most part, geysers are located in three regions of the world : New Zealand, Iceland, and the Yellowstone National Park area of the United States. The most famous geyser in the world is Old Faithful in Yellowstone Park. Old Faithful erupts almost every hour, rising to a height of 125 to 170 feet and expelling more then ten thousand gallons during each eruption1.
1. In order for a geyser to erupt,.................
.A. Hot rocks must rise to the sufface of the earth
B. water must flow underground
C. it must be a warm day
D. the earth must not be rugged or broken
2. Old Faithful is located in.....................
A. New Zeland
B. Iceland
C. the united States
D.England
3. Old Faithful erupts...................... 
A. every 10 minutes 
B. every 60 minutes 
C. every 125 minutes 
D. every 170 minutes 
4. A geyser is...................
A. hot water and steam
B. cracks and fissures
C. hot rocks 
D. great pressure
5. As depth increases,......................
.A. pressure increases but temperature does not
B. temperature increases but pressure does not
C. both pressure and temperature increase
D. neither pressure nor temperature increases

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