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WorksheetsKung Fu Panda (June 22 & 23 Earth Science Regents MCQs)
Total questions: 101
Worksheet time: 5hrs 3mins
Astronomers have determined that the star Arcturus has a surface temperature of 4560 K and a luminosity of 170. Based on these characteristics, Arcturus is classified as which type of star?
giant
supergiant
white dwarf
main sequence
The image below shows the near-Earth asteroid Itokawa. Which surface feature would be created if Itokawa hit Earth’s surface?
volcanic crater
impact crater
mountain valley
rift valley
The north end of Earth’s axis of rotation points toward
Alpha Centauri
Spica
Polaris
Betelgeuse
What is the approximate percentage of Earth’s surface that is covered by the hydrosphere?
10%
50%
70%
90%
The table below shows the times of high tides and low tides for a coastal location.
How much time occurred between the high tides on this day?
approximately 6.5 hours
a little less than 12 hours
almost 12.5 hours
a little more than 24 hours
The map below shows a weather variable recorded at the same time across the United States. According to the data on the map, which weather variable was most likely recorded?
wind speed in knots
air pressure in millibars
rainfall in inches in the last 6 hours
air temperature in degrees Fahrenheit
The table below shows the dates of peak activity of four meteor showers for five different years. Meteor showers are named for the constellations in which they appear to originate, as observed from Earth. Based on the data, the dates of these meteor showers appear to depend on the
position of Earth in its orbit
phase of the Moon during the month
turning of Earth on its axis
movement of meteors in their orbits
The diagram below represents four different land surfaces of equal area. Which area would most likely have the greatest permeability as each area receives the same amount of rainfall?
sand
forest with clay soil
pebbles
grassy field with silt soil
The diagram below represents a portion of the water cycle. Letters A, B, C, and D represent processes or features related to the water cycle. Arrows represent movement of water. Which table correctly matches these letters with the processes or features related to the water cycle?
The leading edge of a thunderstorm reached Elmira, New York, at 1:00 p.m. This thunderstorm was moving eastward at 45 miles per hour. The leading edge of the thunderstorm most likely reached Binghamton, New York, at approximately
1:00 p.m.
12:00 p.m.
2:00 p.m.
4:00 p.m.
An air temperature of 30°C is equal to
–1°F
83°F
68°F
86°F
The subtropical jet streams are fast flowing air currents located in the atmosphere about 10 kilometers above the surface of Earth. In which layer of the atmosphere are the subtropical streams located?
stratosphere
troposphere
mesosphere
thermosphere
Which substance given off by a volcano is most likely to cause global cooling following a large volcanic eruption?
carbon dioxide
methane
water vapor
airborne ash
The table below shows general climate conditions of four different locations, A, B, C, and D. In which location is chemical weathering probably greatest, based on these climate conditions?
A
B
C
D
The picture shows a calorimeter being used to demonstrate a method of heat transfer. One cup is filled with hot water, and the other cup is filled with cold water. A metal bar extends through the lids into the water in both cups. Thermometers record changes in temperature. This calorimeter demonstrates the transfer of heat through the metal bar from
cold water to hot water by conduction
hot water to cold water by radiation
hot water to cold water by conduction
cold water to hot water by radiation
At the end of which geologic time period were the continents of South America and Africa joined together and entirely located south of the equator?
Paleogene Period
Jurassic Period
Permian Period
Devonian Period
Which atmospheric cross section best represents the general air circulation over the North Pole?
1
2
3
4
The diagram below represents a sling psychrometer. Based on the wet-bulb temperature and the dry-bulb temperature, what is the approximate relative humidity?
6%
30%
8%
60%
The graph below represents the decay of a radioactive isotope into a stable disintegration product. Which remains could be dated using this radioactive isotope?
seeds from the earliest grasses
Naples tree trunk
feathers from the earliest birds
mastodont bone
Block diagram A below represents normal surface ocean currents and the upwelling of colder water in the eastern Pacific Ocean. Block diagram B represents a reversal of surface ocean currents and decreased upwelling in the same region, initiating an El Niño event. Warmer surface water builds up in the eastern Pacific Ocean during an El Niño event because the speed of the Easterlies
decreases and upwelling decreases
decreases and upwelling increases
increases and upwelling decreases
increases and upwelling increases
Ordovician-age crinoid fossils of tropical marine origin are found in the bedrock of the Hudson- Mohawk lowlands region of New York State. This provides evidence that New York State was once located at a
lower latitude and lower elevation
lower latitude and higher elevation
higher latitude and lower elevation
higher latitude and higher elevation
The photograph below shows the New York State fossil Eurypterus remipes. Eurypterus fossils are most likely to be found in surface bedrock near
Mt. Marcy
Watertown
Niagara Falls
The study of fossil evidence suggests that humans
lived on the continent of Pangaea
have existed during most of geologic time
have existed for a very brief time in geologic
history
lived at the same time as dinosaurs
What is occurring at the Southeast Indian Ridge?
New oceanic crust is forming.
Old continental crust is being destroyed.
New continental crust is forming.
Old oceanic crust is being destroyed.
The cross sections below represent two rock outcrops labeled I and II. Letters A, B, C, D, and X identify rock layers. The rock layers have not been overturned. Which rock layer in outcrop II best correlates with layer X in outcrop I?
A
B
C
D
Which igneous rock formed from magma that cooled slowly and is composed of 5% amphibole, 8% biotite, 15% plagioclase feldspar, 37% quartz, and 35% potassium feldspar?
rhyolite
granite
diorite
scoria
A mudslide is most likely to occur on a hillslope having soil that is
saturated with water and without vegetation
unsaturated and covered by vegetation
unsaturated and without vegetation
saturated with water and covered by
vegetation
The map below represents portions of three tectonic plates. Points A through D represent locations on Earth’s surface. Which location is closest to a zone of rifting?
A
B
C
D
The table below shows the chemical formulas for four rock-forming minerals. Which mineral contains the two most abundant elements by mass in Earth’s crust?
chalcopyrite
barite
apatite
fayalite
The map below represents a bridge over the meander of a stream. From the bridge, a student measures the stream velocity at locations A, B, and C. Which table represents the most probable stream velocity recordings at each location?
The sequence of diagrams below represent three 34 stages in the formation of a geologic feature over time. Which geologic feature is formed by this process?
drumlin
kettle lake
dune
finger lake
Which mineral has cleavage in two directions and is commonly used to manufacture ceramics?
muscovite mica
olivine
fluorite
potassium feldspar
A mixture of rounded pebbles and sand was deposited in a river. Over time, these sediments were compacted and cemented together to form the sedimentary rock
conglomerate
shale
breccia
sandstone
The map below shows a portion of Matagorda Island. This barrier island is located along the coast of Texas in the Gulf of Mexico. Which agent of erosion is primarily responsible for the formation of Matagorda Island?
streams
wind
moving ice
wave action
A primary difference between sedimentary rocks and nonsedimentary rocks is that
nonsedimentary rocks contain an abundance of fossils
sedimentary rocks are formed at plate bound- aries
sedimentary rocks are currently found only in marine locations
nonsedimentary rocks originate in regions of great heat and/or pressure
The data table describes some types of limestone. Which limestone is classified as inorganic?
chalk
travertine
coquina
coral
The data table describes some types of limestone. The photograph below the data table shows one type of limestone described in the table. This type of limestone is best identified as
coquina
chalk
travertine
coral
The photograph shows anorthositic gneiss bedrock from Whiteface Mountain in New York State.
Whiteface Mountain, located in the Mount Marcy region, is one of New York State’s highest mountain peaks. Most of the surface bedrock on Whiteface is anorthositic gneiss made up of large, light-colored plagioclase feldspar crystals and dark mineral bands composed of amphibole, pyroxene, and garnet. The foliated crystal alignment in the gneiss was produced during a major tectonic event called the Grenville orogeny. Landslides have exposed steep slopes of this white and gray bedrock on the sides of Whiteface Mountain.
In the anorthositic gneiss, the mineral garnet is most likely observed in the
dark bands, has a red color, and has a hardness of 7.0
dark bands, has a silver color, and has a hardness of 3.0
light bands, has a red color, and has a hardness of 3.0
light bands, has a silver color, and has a hardness of 7.0
The photograph shows anorthositic gneiss bedrock from Whiteface Mountain in New York State.
Whiteface Mountain, located in the Mount Marcy region, is one of New York State’s highest mountain peaks. Most of the surface bedrock on Whiteface is anorthositic gneiss made up of large, light-colored plagioclase feldspar crystals and dark mineral bands composed of amphibole, pyroxene, and garnet. The foliated crystal alignment in the gneiss was produced during a major tectonic event called the Grenville orogeny. Landslides have exposed steep slopes of this white and gray bedrock on the sides of Whiteface Mountain.
The texture of the gneiss indicates that the bedrock
underwent contact metamorphism
was composed of compacted sediment
underwent regional metamorphism
was bioclastic in origin
The photograph shows anorthositic gneiss bedrock from Whiteface Mountain in New York State.
Whiteface Mountain, located in the Mount Marcy region, is one of New York State’s highest mountain peaks. Most of the surface bedrock on Whiteface is anorthositic gneiss made up of large, light-colored plagioclase feldspar crystals and dark mineral bands composed of amphibole, pyroxene, and garnet. The foliated crystal alignment in the gneiss was produced during a major tectonic event called the Grenville orogeny. Landslides have exposed steep slopes of this white and gray bedrock on the sides of Whiteface Mountain.
The altitude of Polaris as seen by an observer on Whiteface Mountain in the Mount Marcy region will be approximately
40°
90°
74°
44°
The cross section represents a section of Earth’s lithosphere along the coast of Japan. The epicenter of a large magnitude earthquake that occurred on March 11, 2011 is indicated. Devastation occurred mainly in the low-lying coastal areas of Japan closest to the epicenter. Letter A represents a geologic feature.
Which type of tectonic plate boundary is represented in the cross-section?
complex
transform
divergent
convergent
The cross section represents a section of Earth’s lithosphere along the coast of Japan. The epicenter of a large magnitude earthquake that occurred on March 11, 2011 is indicated. Devastation occurred mainly in the low-lying coastal areas of Japan closest to the epicenter. Letter A represents a geologic feature.
The geologic feature indicated by letter A is
an ocean trench
an igneous intrusion
hotspot
island arc
The cross section represents a section of Earth’s lithosphere along the coast of Japan. The epicenter of a large magnitude earthquake that occurred on March 11, 2011 is indicated. Devastation occurred mainly in the low-lying coastal areas of Japan closest to the epicenter. Letter A represents a geologic feature.
What most likely caused the major devastation along the flat coastal areas of Japan as a result of this earthquake?
crustal downwarping
a tsunami
landslides
lava flows
The cross section represents the effect of Earth’s atmosphere on energy from the Sun. Arrows labeled A, B, C, D, and E represent some possible paths of this insolation. The dashed arrows represent energy reradiated from Earth’s surface.
Which arrows represent reflected insolation?
A & E
B & C
D & A
C & D
The cross section represents the effect of Earth’s atmosphere on energy from the Sun. Arrows labeled A, B, C, D, and E represent some possible paths of this insolation. The dashed arrows represent energy reradiated from Earth’s surface.
Compared to path D, the amount of energy reaching Earth’s surface following path B is likely
less, because atmospheric transparency is less
more, because atmospheric transparency is greater
more, because atmospheric transparency is less
less, because atmospheric transparency is greater
The cross section represents the effect of Earth’s atmosphere on energy from the Sun. Arrows labeled A, B, C, D, and E represent some possible paths of this insolation. The dashed arrows represent energy reradiated from Earth’s surface.
Which type of surface material absorbs and reradiates the greatest amount of energy?
white with a smooth texture
dark with a rough texture
dark with a smooth texture
white with a rough texture
The graph shows the number of families (groups of closely related species) represented in the fossil record and five major mass extinction events in Earth’s history.
Which group of living organisms survived all five major mass extinctions?
ammonoids
trilobites
brachiopods
graptolites
The graph shows the number of families (groups of closely related species) represented in the fossil record and five major mass extinction events in Earth’s history.
One group of organisms that existed on Earth before 550 million years ago was
sharks
Burgess shale fauna
Ediacaran fauna
insects
The diagram represents the apparent change in direction of the swing of a scientific device over a period of five hours. This device provides evidence of Earth’s rotation.
Which diagram represents the correct direction of Earth’s rotation?
sharks
Burgess shale fauna
Ediacaran fauna
insects
The diagram represents the apparent change in direction of the swing of a scientific device over a period of five hours. This device provides evidence of Earth’s rotation.
Approximately how many degrees does Earth rotate on its axis over this five-hour period?
15°
45°
75°
90°
The block diagram represents an east coast location near the southern tip of South America. Arrows represent incoming and outgoing radiation.
How are the relative daytime air temperature and the relative daytime air pressure over the beach and ocean are different in the summer months
Beach Temp = HIGH
Beach Pressure = LOW
Ocean Temp = HIGH
Ocean Pressure = LOW
Beach Temp = HIGH
Beach Pressure = LOW
Ocean Temp = LOW
Ocean Pressure = HIGH
Beach Temp = HIGH
Beach Pressure = HIGH
Ocean Temp = LOW
Ocean Pressure = LOW
Beach Temp = LOW
Beach Pressure = LOW
Ocean Temp = LOW
Ocean Pressure = LOW
Which two characteristics classify Jupiter as a Jovian planet?
low density and large diameter
low density and small diameter
high density and large diameter
high density and small diameter
As observed from Earth, the wavelengths of light from the most distant galaxies are usually
blue shifted due to an expanding universe
blue shifted due to a contracting universe
red shifted due to an expanding universe
red shifted due to a contracting universe
The rate of Earth’s revolution around the Sun is approximately
1°/day
15°/day
24°/day
360°/day
Different star constellations are observed from Earth at different times during the year because
constellations spin on an axis
constellations travel in an orbit around the Sun
Earth spins on its axis
Earth travels in an orbit around the Sun
The apparent change in the direction of swing of a Foucault pendulum provides evidence of Earth’s
rotation
revolution
tilted axis
elliptical orbit
The Milky Way can best be described as
an elliptical galaxy
a collection of stars orbiting the Sun
a star that originated 4600 million years ago
one of billions of galaxies in the universe
How much heat energy is required to change five grams of ice to liquid water at 0°C?
334 joules
1670 joules
2260 joules
11,300 joules
What is the cause and its effect on the change in mass of the potted plant over time?
Transpiration caused a decrease in mass.
Condensation caused a decrease in mass.
Transpiration caused an increase in mass.
Condensation caused an increase in mass.
Air temperatures are recorded as a weather balloon rises from Earth’s surface. At first, the air temperature constantly decreases for 12 kilometers, then remains constant briefly before increasing for another 12 kilometers before the balloon bursts. In which layer did the balloon burst?
troposphere
stratosphere
mesosphere
thermosphere
The diagram below represents the Moon passing through the darker part of Earth's shadow called the umbra. Letters A and B represent locations on Earth's surface. Which statement best identifies this event and at which location it would be viewed?
A solar eclipse is occurring and can be seen from location A.
A solar eclipse is occurring and can be seen from location B.
A lunar eclipse is occurring and can be seen from location A.
A lunar eclipse is occurring and can be seen from location B.
The photograph below shows an impact crater located in the southwestern United States. This crater most likely formed as a result of
an explosive volcanic eruption
the subduction at a plate boundary
an asteroid colliding with Earth
the evaporation of water from a lake
The diagrams below represent three containers, A, B, and C, which were filled with equal volumes of uniformly sorted plastic beads. To determine porosity, water was poured into each container until the water level rose to the top of the beads. The porosity (art of pore space) was found to be
greatest in container A
greatest in container B
greatest in container C
the same in all three containers
Which cross section represents the cloud patterns and the direction of air movement at a warm front?
[Diagram 1]
[Diagram 2]
[Diagram 3]
[Diagram 4]
Which map shows the most likely path of a low pressure system (L) in the United States if it follows a normal storm track?
1
2
3
4
Which weather instrument is an anemometer?
1
2
3
4
The station model below represents some weather information for a location in New York State. Based on the information on the station model, the weather at this location is
partly cloudy and windy with blowing snow
cloudy and windy with thunderstorms
cloudy and calm with visibility of 2 miles
partly cloudy and calm with an air temperature of 73°F
Electromagnetic energy travels through space from the Sun to the top of Earth’s atmosphere by
conduction
radiation
convection
infiltration
The diagram below represents the position of Earth with respect to the Sun on March 21. A and B are two locations on Earth’s surface. The intensity of insolation over the next three months will
decrease for both A and B
decrease for A and increase for B
increase for both A and B
increase for A and decrease for B
Which event is primarily responsible for the production of oxygen that first entered into Earth’s early atmosphere?
evolution of oxygen-producing organisms
radioactive decay of isotopes producing oxygen
separation of oxygen from hydrogen in water
oxygen-rich comets impacting Earth
Since the break up of Pangaea, it has been inferred that the continent of North America has been generally moving toward the
northwest
northeast
southwest
southeast
The fossil Mucrospirifer is considered to be an index fossil because it existed over a
small geographic region for a long period of time
small geographic region for a short period of time
large geographic region for a long period of time
large geographic region for a short period of time
Compared to Earth’s outer core, the inner core properties are inferred to be
less dense and a solid
less dense and a liquid
more dense and a solid
more dense and a liquid
A seismic station 4000 kilometers from the epicenter of an earthquake records the arrival time of the first S-wave at 1:05:40 p.m. At what time did the first P-wave arrive at this station?
12:58:40 p.m.
1:00:00 p.m.
1:05:40 p.m.
1:11:20 p.m.
The photograph below shows fossilized ammonoids in a rock outcrop. The presence of these fossils in the outcrop indicates that in the past, this region was most likely covered by
desert sand
ocean water
glacial ice
molten rock
The cross section below represents rock units within Earth's crust. Sedimentary rock layers are labeled 1 through 6. The age of the igneous rock is
older than rock layers 1 and 2
the same age as rock layer 3
older than rock layer 3
younger than rock layers 4, 5, and 6
The maps below show different stream drainage patterns. What factor most likely causes these different stream drainage patterns?
age of bedrock
bedrock structure
types of fossils found in the bedrock
temperature variations in the bedrock
The photograph below shows boulders and other sediments that slid down a hillside. This rock slide is most likely an example of
mass movement due to prolonged periods of heavy traffic
mass movement following prolonged periods of heavy rain
abrasion by prolonged exposure to moving ice
abrasion following prolonged exposure to wind action
The Mariana Trench is Earth’s deepest oceanic trench. This trench formed as the Pacific Plate was
overriding the Philippine Plate
overriding the Eurasian Plate
subducting under the Philippine Plate
subducting under the Eurasian Plate
The diagram below represents patterns of normal and reverse magnetic polarity in seafloor bedrock. In which bedrock type and location can this magnetic pattern most likely be observed?
igneous bedrock at the East Pacific Ridge
igneous bedrock at the Tasman Hot Spot
sedimentary bedrock at the East Pacific Ridge
sedimentary bedrock at the Tasman Hot Spot
Compared to the thickness and density of the continental crust, the relative thickness and density of Earth’s oceanic crust are
thinner and less dense
thinner and more dense
thicker and less dense
thicker and more dense
Iron found in some minerals in basalt can react with oxygen and break down into iron oxide particles. This change is an example of
deposition
erosion
chemical weathering
physical weathering
Which feature provides the best evidence that thick glacial ice sheets once advanced southward over New York State?
parallel grooves in bedrock
sorted layers of sediments
caves found in limestone bedrock
V-shaped valleys
The photograph below shows the metamorphic rock gneiss. Three minerals that would most likely be found in this rock are
pyroxene, calcite, and fluorite
garnet, hornblende, and talc
amphibole, augite, and hematite
quartz, mica, and feldspar
Which igneous rock has a fine-grained texture and would have a mineral composition of 57% plagioclase feldspar, 28% amphibole, and 15% biotite?
gabbro
pegmatite
scoria
andesite
What is a common use of the mineral composed of Fe₃Al₂Si₃O₁₂?
ceramics
building stones
plaster of paris
Spring tides are extremely high tides that occur when Earth, the Moon, and the Sun are aligned. A king tide is the common name given to an extremely high spring tide that occurs at perigee (when the Moon is closest to Earth in its orbit). King tides occur onceor twice every year. Normal high tides are now reaching higher and extending farther inland than in the past because of global climate change and rising sea levels. This causes low-lying shorelines to be at an increased risk of flooding. If climate continues to change and sea levels rise,
spring tides and king tides will have a greater effect on shorelines and coastal flooding.
Which diagram best illustrates the positions of Earth (E), the Sun (S), and the Moon (M), and the relative distance between Earth and the Moon that results in a king tide?
[Diagram 1]
[Diagram 2]
[Diagram 3]
[Diagram 4]
Spring tides are extremely high tides that occur when Earth, the Moon, and the Sun are aligned. A king tide is the common name given to an extremely high spring tide that occurs at perigee (when the Moon is closest to Earth in its orbit). King tides occur once or twice every year. Normal high tides are now reaching higher and extending farther inland than in the past because of global climate change and rising sea levels. This causes low-lying shorelines to be at an increased risk of flooding. If climate continues to change and sea levels rise, spring tides and king tides will have a greater effect on shorelines and coastal flooding.
A coastal community can make advanced preparations for a king tide event because the motions of Earth and the Moon are
cyclic and predictable
cyclic and unpredictable
noncyclic and predictable
noncyclic and unpredictable
Spring tides are extremely high tides that occur when Earth, the Moon, and the Sun are aligned. A king tide is the common name given to an extremely high spring tide that occurs at perigee (when the Moon is closest to Earth in its orbit). King tides occur once or twice every year. Normal high tides are now reaching higher and extending farther inland than in the past because of global climate change and rising sea levels. This causes low-lying shorelines to be at an increased risk of flooding. If climate continues to change and sea levels rise, spring tides and king tides will have a greater effect on shorelines and coastal flooding.
Which factor is primarily causing global average sea levels to rise over time?
decreased incoming solar radiation
decreased ocean water temperature
increased amount of snowfall in Arctic regions
increased melting of glacial ice
Two major greenhouse gases that may be linked to global warming are
carbon dioxide and nitrogen
carbon dioxide and methane
oxygen and nitrogen
oxygen and methane
The map shows the four time zones and some latitude and longitude lines across the continental United States. Some cities are labeled on the map.
What time is it in Buffalo, New York, when it is 5:00 p.m. in Omaha, Nebraska?
6:00 p.m.
7:00 p.m.
3:00 p.m.
4:00 p.m.
The map shows the four time zones and some latitude and longitude lines across the continental United States Some cities are labeled on the map.
The altitude of Polaris, as measured by an observer in Reno, Nevada, is closest to
39°
41°
119°
121°
The map shows the four time zones and some latitude and longitude lines across the continental United States. Some cities are labeled on the map.
Which city has the shortest duration of insolation on December 21?
Mobile
Omaha
Miami
Seattle
The map shows the four time zones and some latitude and longitude lines across the continental United States. Some cities are labeled on the map.
The four time zones shown on the map are based on Earth’s
tilted axis
orbital velocity
rate of rotation
rate of revolution
The pie chart shows percentages of different rock types used to make crushed stone in the United States during 2017. Crushed Stone is the world’s most basic mineral commodity. It is abundant, widely available, and inexpensive. In 2017, the United States produced 1.3 billion tons of crushed stone, most of which is used in highway and building construction.
Which two elements are common to both rocks that make up the 4% section of the United States crushed stone rock types?
aluminum and iron
silicon and oxygen
calcium and magnesium
nitrogen and potassium
The pie chart shows percentages of different rock types used to make crushed stone in the United States during 2017. Crushed Stone is the world’s most basic mineral commodity. It is abundant, widely available, and inexpensive. In 2017, the United States produced 1.3 billion tons of crushed stone, most of which is used in highway and building construction.
Which rock would most likely be included in trap rock?
phyllite
obsidian
diabase
rhyolite
The pie chart shows percentages of different rock types used to make crushed stone in the United States during 2017. Crushed Stone is the world’s most basic mineral commodity. It is abundant, widely available, and inexpensive. In 2017, the United States produced 1.3 billion tons of crushed stone, most of which is used in highway and building construction.
Which crushed rock would most likely weather the fastest in areas that receive high levels of acidic rain?
trap rock
granite
quartzite
limestone
When the driver of a dump truck raises the bed of the dump truck to release its load, quartzite tends to scratch the bottom and sides of the bed easier than limestone. Which property of the minerals in quartzite causes them to more easily scratch the bed of the dump truck?
streak
luster
hardness
cleavage
One reason why carbon-14 was used to determine the age of the woolly rhinoceros tooth was because carbon-14
never completely decays
has a very long half-life
can be found in most organic remains
is easily identified in Carboniferous bedrock
The data table lists samples of three different materials, the age of each sample, the radioactive isotope used to date each sample, and the location where the sample was found.
Approximately how much of the original uranium-238 is left in the sample of zircon crystals?
100%
50%
25%
12.5%
The iridium-enriched sediment layer was deposited at the end of which geological period?
Permian
Paleogene
Quaternary
Cretaceous
