What percentage of the earth's atmosphere does O2 comprise? w) 75% x) 50% y) 21% z) 32%

What percentage of the earth's atmosphere does O2 comprise? w) 75% x) 50% y) 21% z) 32%
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ANSWER: Y -- 21%
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The continental shelves comprise what percentage o the Earth's total land area? w) 38 percent x) 28 percent y) 18 percent z) 8 percent

Description : The continental shelves comprise what percentage o the Earth's total land area? w) 38 percent x) 28 percent y) 18 percent z) 8 percent

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What percentage of the earth's water is fresh water? w) 50% x) 22% y) 7% z) 3%

Description : What percentage of the earth's water is fresh water? w) 50% x) 22% y) 7% z) 3%

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Description : Of the energy used in the United States, about wha percent is provided by hydroelectric power? w) 4% x) 20% y) 50% z) 75%

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The oxygen in the earth's atmosphere was probably produced by which of the following? w) volcanos x) photosynthetic organisms y) radioactive minerals z) meteors

Description : The oxygen in the earth's atmosphere was probably produced by which of the following? w) volcanos x) photosynthetic organisms y) radioactive minerals z) meteors

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Description : The jet-stream lies between which two layers of th earth's atmosphere? w) thermosphere and ionosphere x) mesosphere and thermosphere y) troposphere and stratosphere z) stratosphere and mesosphere

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Which of the following is the approximate ratio of the area of the continents to the area of the earth's oceans? w) 2:1 x) 1:1 y) 2:5 z) 1:10

Description : Which of the following is the approximate ratio of the area of the continents to the area of the earth's oceans? w) 2:1 x) 1:1 y) 2:5 z) 1:10

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Description : Which of the following is TRUE of an earthquake's epicenter and focus? w) they are the same x) the focus is above the epicenter y) the epicenter is at the earth's surface z) the focus is at the earth's inner core

Last Answer : ANSWER: Y -- THE EPICENTER IS AT THE EARTH'S SURFACE

Which of these events gives us evidence that the earth is spherical? w) a volcanic eruption x) an earthquake y) an eclipse of the moon z) the earth's rotation

Description : Which of these events gives us evidence that the earth is spherical? w) a volcanic eruption x) an earthquake y) an eclipse of the moon z) the earth's rotation

Last Answer : ANSWER: Y -- AN ECLIPSE OF THE MOON

Which of the following causes the oblate spheroid shape of the earth? w) the earth's magnetism x) the earth's gravity y) the earth's rotation z) the moon's tidal pull

Description : Which of the following causes the oblate spheroid shape of the earth? w) the earth's magnetism x) the earth's gravity y) the earth's rotation z) the moon's tidal pull

Last Answer : ANSWER: Y -- THE EARTH'S ROTATION

Which element in chlorofluorocarbons (CFCs) is responsible for destroying the Earth's ozone layer? w) oxygen x) fluorine y) chlorine z) bromine

Description : Which element in chlorofluorocarbons (CFCs) is responsible for destroying the Earth's ozone layer? w) oxygen x) fluorine y) chlorine z) bromine

Last Answer : ANSWER: Y -- CHLORINE

Which of the following elements is found in the earth's crust as both a native element and as a compound? w) argon x) copper y) chlorine z) silicon

Description : Which of the following elements is found in the earth's crust as both a native element and as a compound? w) argon x) copper y) chlorine z) silicon

Last Answer : ANSWER: X -- COPPER

In geological studies, a fault in the earth's surface in which the hanging wall has moved down relative to the footwall is termed: w) normal fault x) reverse fault y) upthrust fault z) none of these

Description : In geological studies, a fault in the earth's surface in which the hanging wall has moved down relative to the footwall is termed: w) normal fault x) reverse fault y) upthrust fault z) none of these

Last Answer : ANSWER: W -- NORMAL FAULT

In geological studies, a fracture in the earth's surface along which movement has taken place is termed: w) tension fracture x) gash fracture y) fault z) none of these

Description : In geological studies, a fracture in the earth's surface along which movement has taken place is termed: w) tension fracture x) gash fracture y) fault z) none of these

Last Answer : ANSWER: Y -- FAULT

The earth's average density is: w) 2.82 grams per cubic centimeter x) 4.75 grams per cubic centimeter y) 5.52 grams per cubic centimeter z) 10.5 grams per cubic centimeter

Description : The earth's average density is: w) 2.82 grams per cubic centimeter x) 4.75 grams per cubic centimeter y) 5.52 grams per cubic centimeter z) 10.5 grams per cubic centimeter 

Last Answer : ANSWER: Y -- 5.52 GRAMS PER CUBIC CENTIMETER

Molten rock beneath the Earth's crust is called: w) magma x) liquicite y) lava z) igneous

Description : Molten rock beneath the Earth's crust is called: w) magma x) liquicite y) lava z) igneous

Last Answer : ANSWER: W -- MAGMA

If all the Earth's ice melted, the increase in sea level would be approximately: w) 100 meters x) 2 meters y) 70 meters z) 20 meters

Description : If all the Earth's ice melted, the increase in sea level would be approximately: w) 100 meters x) 2 meters y) 70 meters z) 20 meters

Last Answer : ANSWER: Y -- 70 METERS

In geological studies, a fault in the earth's surface in which the hanging wall has moved UP relative to the footwall is termed: w) overthrust fault x) reverse fault y) tear fault z) none of these

Description : In geological studies, a fault in the earth's surface in which the hanging wall has moved UP relative to the footwall is termed: w) overthrust fault x) reverse fault y) tear fault z) none of these

Last Answer : ANSWER: X -- REVERSE FAULT 

During which period, in the earth's history, did MOST dinosaurs become extinct? w) Carboniferous x) Cretaceous y) Quaternary z) Triassic

Description : During which period, in the earth's history, did MOST dinosaurs become extinct? w) Carboniferous x) Cretaceous y) Quaternary z) Triassic

Last Answer : ANSWER: X -- CRETACEOUS

The Greenhouse Effect is caused primarily by which of the following processes? w) blocking incoming short wave solar energy x) absorbing incoming short wave solar energy y) heating of the Earth's stratosphere z) absorbing outgoing long wave radiation from the Earth

Description : The Greenhouse Effect is caused primarily by which of the following processes? w) blocking incoming short wave solar energy x) absorbing incoming short wave solar energy y) heating of the Earth's stratosphere z) absorbing outgoing long wave radiation from the Earth

Last Answer : ANSWER: Z -- ABSORBING OUTGOING LONG WAVE RADIATION FROM THE EARTH 

The earth's climate has been warming since the las glacial period which ended about how many years ago? w) 1,000 to 2,000 years ago x) 10,000 to 20,000 years ago y) 100,000 to 200,000 years ago z) 1,000,000 to 2,000,000 years ago

Description : The earth's climate has been warming since the las glacial period which ended about how many years ago? w) 1,000 to 2,000 years ago x) 10,000 to 20,000 years ago y) 100,000 to 200,000 years ago z) 1,000,000 to 2,000,000 years ago

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What name is given to the science which studies the atmosphere? w) oceanography x) atmospherology y) meteorology z) weatherology

Description : What name is given to the science which studies the atmosphere? w) oceanography x) atmospherology y) meteorology z) weatherology

Last Answer : ANSWER: Y -- METEOROLOGY

The concentration of carbon dioxide in the atmosphere is in the range of: w) 1-10 parts per million x) 10-100 parts per million y) 100-1000 parts per million z) 1000-10,000 parts per million

Description : The concentration of carbon dioxide in the atmosphere is in the range of: w) 1-10 parts per million x) 10-100 parts per million y) 100-1000 parts per million z) 1000-10,000 parts per million

Last Answer : ANSWER: Y -- 100-1000 PARTS PER MILLION (the exact number is 350 ppm as of the time of this article)

While many different gases are found in the atmosphere, a number do NOT contribute significantly to solar heating of the atmosphere. Which TWO of the following gases do NOT absorb much heat? w) carbon dioxide x) nitrogen y) water vapor z) oxygen

Description : While many different gases are found in the atmosphere, a number do NOT contribute significantly to solar heating of the atmosphere. Which TWO of the following gases do NOT absorb much heat? w) carbon dioxide x) nitrogen y) water vapor z) oxygen

Last Answer : ANSWER: X and Z -- NITROGEN and OXYGEN

The density of lead is 12 grams per cm3. A lead brick has a mass of 1.5 kilograms. Its dimensions are 10 cm by 5 cm by 4 cm. Is it: w) More than 75% hollow x) Between 50 and 75% hollow y) Between 25 and 50% hollow z) Between 0 and 25% hollow

Description : The density of lead is 12 grams per cm3. A lead brick has a mass of 1.5 kilograms. Its dimensions are 10 cm by 5 cm by 4 cm. Is it: w) More than 75% hollow x) Between 50 and 75% hollow y) Between 25 and 50% hollow z) Between 0 and 25% hollow

Last Answer : ANSWER: Y -- BETWEEN 25 AND 50% HOLLOW

Air contain 21% O2 and 79% N2 by volume. Calculate the composition in terms percentage by weight.

Description : Air contain 21% O2 and 79% N2 by volume. Calculate the composition in terms percentage by weight.

Last Answer : Basis: 100 kmole air Kmoles of O2 =21 Kmoles of N2 =79 Weight of O2 =21x32=672 kg Weight of N2 =79x28=2212 kg Total weight =2884 kg Weight% of O2 = (weight of O2/ total weight)x100  = (672/2884)x100  = 23.3% Weight% of N2 =(weight of N2/ total weight)x100  = (2212/2884)x100  = 76.7%

What is the name of the phenomenon that causes an accumulation of heat in the lower atmosphere because of the absorption of longwave radiation from the Earth's surface?

Description : What is the name of the phenomenon that causes an accumulation of heat in the lower atmosphere because of the absorption of longwave radiation from the Earth's surface?

Last Answer : ANSWER: GREENHOUSE EFFECT

Pangaea is the name of a former continent that included: w) all the continents x) only Europe and Asia y) only South America and Africa z) only North and South America

Description : Pangaea is the name of a former continent that included: w) all the continents x) only Europe and Asia y) only South America and Africa z) only North and South America

Last Answer : ANSWER: W -- ALL THE CONTINENTS

What mineral is the most dense? w) hematite x) cinnabar y) marcasite z) rhodochrosite

Description : What mineral is the most dense? w) hematite x) cinnabar y) marcasite z) rhodochrosite

Last Answer : ANSWER: X -- CINNABAR

Which of the following mountain ranges was formed during the Mesozoic era? w) Rocky Mountains x) Cascades y) Appalachian z) Sierra Nevada

Description : Which of the following mountain ranges was formed during the Mesozoic era? w) Rocky Mountains x) Cascades y) Appalachian z) Sierra Nevada

Last Answer : ANSWER: Z -- SIERRA NEVADA

Sulfuric acid aerosols from the eruption of Mt. Pinatubo reduced the rate of global warming last year. They also contributed to the record size of: w) acid rainfalls in Europe x) the anchovy catch off Peru y) the ozone hole over Antarctica z) fish kills in the Amazon River

Description : Sulfuric acid aerosols from the eruption of Mt. Pinatubo reduced the rate of global warming last year. They also contributed to the record size of: w) acid rainfalls in Europe x) the anchovy catch off Peru y) the ozone hole over Antarctica z) fish kills in the Amazon River

Last Answer : ANSWER: Y -- THE OZONE HOLE OVER ANTARCTICA

Cloud droplets unite most easily to form raindrops in clouds containing which of the following substances? w) ozone x) plant pollen y) carbon tetrachloride z) large salt crystals

Description : Cloud droplets unite most easily to form raindrops in clouds containing which of the following substances? w) ozone x) plant pollen y) carbon tetrachloride z) large salt crystals

Last Answer : ANSWER: Z -- LARGE SALT CRYSTALS

Which of the following is an average number of inches of snow equal to one inch of rain? w) 1 inch x) 5 inches y) 10 inches z) 25 inches

Description : Which of the following is an average number of inches of snow equal to one inch of rain? w) 1 inch x) 5 inches y) 10 inches z) 25 inches

Last Answer : ANSWER: Y -- 10 inches

When the difference in the temperature of the wet-bulb thermometer and dry-bulb thermometer is large, what does it indicate about the air? w) it is very dry x) it is nearly saturated y) it is very warm z) it is very cold

Description : When the difference in the temperature of the wet-bulb thermometer and dry-bulb thermometer is large, what does it indicate about the air? w) it is very dry x) it is nearly saturated y) it is very warm z) it is very cold

Last Answer : ANSWER: W -- IT IS VERY DRY

What is considered to be the oldest lake in North America? w) Mono Lake, CA x) Lake Superior, MI y) The Great Salt Lake, UT z) Crater Lake, OR

Description : What is considered to be the oldest lake in North America? w) Mono Lake, CA x) Lake Superior, MI y) The Great Salt Lake, UT z) Crater Lake, OR

Last Answer : ANSWER: W -- MONO LAKE, CA

On which of the following does the capacity of a kilogram of air for holding water depend? w) the air pressure x) the air temperature y) the dust content of the air z) the ions in the air

Description : On which of the following does the capacity of a kilogram of air for holding water depend? w) the air pressure x) the air temperature y) the dust content of the air z) the ions in the air

Last Answer : ANSWER: X -- THE AIR TEMPERATURE 

What is considered to be the approximate difference in average temperature between the "little ice age" and today? w) 1 to 3 degrees centigrade x) 5 to 8 degrees centigrade y) 10 to 12 degrees centigrade z) 15 to 20 degrees centigrade

Description : What is considered to be the approximate difference in average temperature between the "little ice age" and today? w) 1 to 3 degrees centigrade x) 5 to 8 degrees centigrade y) 10 to 12 degrees centigrade z) 15 to 20 degrees centigrade

Last Answer : ANSWER: W -- 1 TO 3 DEGREES CENTIGRADE

What form of runoff is water that flows down a slope within the upper layers of the soil rather than on top of them? w) interflow x) extraflow y) endoflow z) detrital runoff

Description : What form of runoff is water that flows down a slope within the upper layers of the soil rather than on top of them? w) interflow x) extraflow y) endoflow z) detrital runoff

Last Answer : ANSWER: W -- INTERFLOW

When does the air cool most rapidly? Is it during w) a cloudy day x) a cloudy night y) a sunny day z) a clear night

Description : When does the air cool most rapidly? Is it during w) a cloudy day x) a cloudy night y) a sunny day z) a clear night

Last Answer : ANSWER: Z -- A CLEAR NIGHT

The approximate average yearly rainfall in centimeters for the United States is: w) 25 centimeters x) 50 centimeters y) 75 centimeters z) 100 centimeters

Description : The approximate average yearly rainfall in centimeters for the United States is: w) 25 centimeters x) 50 centimeters y) 75 centimeters z) 100 centimeters

Last Answer : ANSWER: Y -- 75 CENTIMETERS

Valleys formed by glaciers always have which of the following characteristics? w) U-shaped cross sections x) straight courses y) uniform slopes z) bedrock floors

Description : Valleys formed by glaciers always have which of the following characteristics? w) U-shaped cross sections x) straight courses y) uniform slopes z) bedrock floors

Last Answer : ANSWER: W -- U-SHAPED CROSS SECTIONS

When the front of a glacier is stationary for a long time, the glacier will do which of the following? w) form many crevasses x) melt away y) not erode its bed z) build a large terminal moraine

Description : When the front of a glacier is stationary for a long time, the glacier will do which of the following? w) form many crevasses x) melt away y) not erode its bed z) build a large terminal moraine

Last Answer : ANSWER: Z -- BUILD A LARGE TERMINAL MORAINE

Carbon dioxide is an important greenhouse gas. What is the current rate in parts per million per year of atmospheric increase of this gas? w) 0.15 ppm per year (parts per million) x) 1.5 ppm per year y) 15 ppm per year z) 150 ppm per year

Description : Carbon dioxide is an important greenhouse gas. What is the current rate in parts per million per year of atmospheric increase of this gas? w) 0.15 ppm per year (parts per million) x) 1.5 ppm per year y) 15 ppm per year z) 150 ppm per year 

Last Answer : ANSWER: X -- 1.5 PPM PER YEAR 

The largest single component, by weight, in the average American landfill is: w) toxic waste x) diapers y) newspapers z) pizza boxes

Description : The largest single component, by weight, in the average American landfill is: w) toxic waste x) diapers y) newspapers z) pizza boxes

Last Answer : ANSWER: Y -- NEWSPAPERS

North American Indians used this mineral of volcanic origin to make tips for arrows: w) obsidian x) quartz y) flint z) pumice

Description : North American Indians used this mineral of volcanic origin to make tips for arrows: w) obsidian x) quartz y) flint z) pumice

Last Answer : ANSWER: W -- OBSIDIAN

Which animal is the center of the timber-harvest controversy in the Pacific Northwest? w) blackfooted ferret x) California condor y) northern spotted owl z) gray wolf

Description : Which animal is the center of the timber-harvest controversy in the Pacific Northwest? w) blackfooted ferret x) California condor y) northern spotted owl z) gray wolf

Last Answer : ANSWER: Y -- NORTHERN SPOTTED OWL

Biomass energy is w) formed through photosynthesis x) caused by heat due to the large mass of the Earth y) has been used for only a few years z) the predominant source of commercial heat energy in the northern regions of the United States

Description : Biomass energy is w) formed through photosynthesis x) caused by heat due to the large mass of the Earth y) has been used for only a few years z) the predominant source of commercial heat energy in the northern regions of the United States

Last Answer : ANSWER: W -- FORMED THROUGH PHOTOSYNTHESIS

In geological studies, the Mohorovicic Discontinuity, commonly called the Moho, is the boundary between the w) the mantle and the crust x) asthenosphere and the mantle y) mantle and the outer core z) outer core and the inner core

Description : In geological studies, the Mohorovicic Discontinuity, commonly called the Moho, is the boundary between the w) the mantle and the crust x) asthenosphere and the mantle y) mantle and the outer core z) outer core and the inner core

Last Answer : ANSWER: W -- THE MANTLE AND THE CRUST

Which of the following distances in kilometers is closest to the diameter of the earth? w) 750 kilometers x) 2,750 kilometers y) 12,750 kilometers z) 127,500 kilometers

Description : Which of the following distances in kilometers is closest to the diameter of the earth? w) 750 kilometers x) 2,750 kilometers y) 12,750 kilometers z) 127,500 kilometers

Last Answer : ANSWER: Y -- 12,750 KILOMETERS 

Safety aside, for which of the following reasons is alcohol used in preference to mercury in a minimum thermometer? w) Alcohol has a higher boiling point x) Alcohol has a lower freezing point y) Alcohol contracts more uniformly z) Alcohol can be dyed for visibility

Description : Safety aside, for which of the following reasons is alcohol used in preference to mercury in a minimum thermometer? w) Alcohol has a higher boiling point x) Alcohol has a lower freezing point y) Alcohol contracts more uniformly z) Alcohol can be dyed for visibility

Last Answer : ANSWER: X -- ALCOHOL HAS A LOWER FREEZING POINT

The core of the earth is thought to be composed of which of the following? w) basalt and granite x) compressed gases y) uranium and lead z) iron and nickel

Description : The core of the earth is thought to be composed of which of the following? w) basalt and granite x) compressed gases y) uranium and lead z) iron and nickel

Last Answer : ANSWER: Z -- IRON AND NICKEL