In paragraph (1) the word POSE is closest in meaning to?
claim
model
assume
present
In paragraph 2, why does the author include the information that dinosaurs had flourished for tens of millions of years and then suddenly disappeared?
To support the claim that the mass extinction at the end of the Cretaceous is the best-documented of the dozen or so mass extinctions in the geological record
To explain why as many as half of the species on Earth at the time are believed to have become extinct at the end of the Cretaceous
To explain why paleontologists have always been intrigued by the mass extinction at the end of the Cretaceous
To provide evidence that an impact can be large enough to disturb the environment of the entire planet and cause an ecological disaster
Which of the following can be inferred from paragraph 3 about the location of the meteorite impact in Mexico?
The location of the impact site in Mexico was kept secret by geologists from 1980 to 1990
It was a well-known fact that the impact had occurred in the Yucatán region
Geologists knew that there had been an impact before they knew where it had occurred.
The Yucatán region was chosen by geologists as the most probable impact site because of its climate.
According to paragraph 3, how did scientists determine that a large meteorite had impacted Earth?
They discovered a large crater in the Yucatán region of Mexico.
They found a unique layer of sediment worldwide.
They were alerted by archaeologists who had been excavating in the Yucatán region.
They located a meteorite with a mass of over a trillion tons
In paragraph 4, the word EXCAVATING is closest to meaning to...
digging out
extending
destroying
covering up
In paragraph 4 the word CONSUMED is closest in meaning to..
changed
exposed
destroyed
covered
According to paragraph 4, all of the following statements are true of the impact at the end of the Cretaceous period EXCEPT:
A large amount of dust blocked sunlight from Earth.
Earth became cold and dark for several months.
New elements were formed in Earth’s crust.
Large quantities of nitric acid were produced.
The phrase "tentatively identified" in paragraph 5 is closest in meaning to...
identified after careful study
identified without certainty
occasionally identified
easily identified
The word perspective in paragraph 6 is closest in meaning to...
sense of values
point of view
calculation
complication
Paragraph 6 supports which of the following statements about the factors that are essential for the survival of a species?
The most important factor for the survival of a species is its ability to compete and adapt to gradual changes in its environment
The ability of a species to compete and adapt to a gradually changing environment is not the only ability that is essential for survival.
Since most extinctions of species are due to major meteorite impacts, the ability to survive such impacts is the most important factor for the survival of a species.
The factors that are most important for the survival of a species vary significantly from one species to another.
According to the passage, who conducted investigations about the current dangers posed by large meteorite impacts on Earth?
Paleontologists
Geologists
The United States Congress
NASA