问答

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[Reading Comprehension]

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文章：

    In addition to conventional galaxies, the universe contains very dim galaxies that until recently went unnoticed by astronomers. Possibly as numerous as conventional galaxies, these galaxies have the same general shape and even the same approximate number of stars as a common type of conventional galaxy, the spiral, but tend to be much larger. Because these galaxies' mass is spread out over larger areas, they have far fewer stars per unit volume than do conventional galaxies. Apparently these low-surface-brightness galaxies, as they are called, take much longer than conventional galaxies to condense their primordial gas and convert it to stars—that is, they evolve much more slowly.

    These galaxies may constitute an answer to the longstanding puzzle of the missing baryonic mass in the universe. Baryons—subatomic particles that are generally protons or neutrons—are the source of stellar, and therefore galactic, luminosity, and so their numbers can be estimated based on how luminous galaxies are. However, the amount of helium in the universe, as measured by spectroscopy, suggests that there are far more baryons in the universe than estimates based on galactic luminosity indicate. Astronomers have long speculated that the missing baryonic mass might eventually be discovered in intergalactic space or as some large population of galaxies that are difficult to detect.

题目：

The primary purpose of the passage is to

选项:

A、describe a phenomenon and consider its scientific significance
B、contrast two phenomena and discuss a puzzling difference between them
C、identify a newly discovered phenomenon and explain its origins
D、compare two classes of objects and discuss the physical properties of each
E、discuss a discovery and point out its inconsistency with existing theory

答案:

A
3答疑

[Critical Reasoning]

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题目：

Astronomer: Observations of the Shoemaker-Levi comet on its collision course with Jupiter showed that the comet broke into fragments before entering Jupiter's atmosphere in 1994, but they did not show how big those fragments were.  In hopes of gaining some indication of the fragments' size, astronomers studied spectrographic analyses of Jupiter's outer atmosphere.  These analyses revealed unprecedented traces of sulfur after the fragments' entry. The fragments themselves almost certainly contained no sulfur, but many astronomers believe that the cloud layer below Jupiter's outer atmosphere does contain sulfur.  Since sulfur would have seeped into the outer atmosphere if comet fragments had penetrated this cloud layer, it is likely that some of the fragments were at least large enough to have passed through Jupiter's outer atmosphere without being burned up.
 
In the astronomer's argument, the two portions in boldface play which of the following roles?

选项:

A、The first presents a circumstance for which the astronomer offers an explanation; the second is part of that explanation.
B、The first acknowledges a consideration that weighs against the conclusion of the argument; the second is that conclusion.
C、The first acknowledges a consideration that weighs against the conclusion of the argument; the second provides evidence in support of that conclusion.
D、The first provides evidence in support of the conclusion of the argument; the second acknowledges a consideration that weighs against that conclusion.
E、The first is a judgment advanced in support of the conclusion of the argument; the second is that conclusion.

答案:

E
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[Critical Reasoning]

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题目：

The art jury will select either Fillmore’s or Clivestone’s sculptures, but not both, for the midwest art show to be held next spring. If Fillmore’s sculptures are chosen, then the show will contain bronze works. If Clivestone’s sculptures are selected, the show will contain sculptures made from stainless steel.
Assuming the statements in the passage are true, which one of the following statements must also be true?

选项:

A、A. The art show might contain no bronze or stainless steel sculptures.
B、B. If the art show contains bronze sculptures, then it is certain that Fillmore's sculptures were chosen for the show.
C、C. The art show will certainly contain either bronze or stainless steel sculptures, and the art show will most certainly not contain both types of sculptures.
D、D. If the art show contains stainless steel sculptures, it is possible, but not certain, that Clivestone's sculptures were selected by the jury for the show.
E、E. If the art show contains neither bronze nor stainless steel sculptures, it is certain that neither Fillmore's nor Clivestone's sculptures were selected for the show.

答案:

D
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[Critical Reasoning]

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题目：

Often patients with ankle fractures that are stable, and thus do not require surgery, are given follow-up x-rays because their orthopedists are concerned about possibly having misjudged the stability of the frac- ture. When a number of follow-up x-rays were reviewed, however, all
the fractures that had initially been judged stable were found to have healed correctly. Therefore, it is a waste of money to order follow-up
x-rays of ankle fracture initially judged stable.
 
Which of the following, if true, most strengthens the argument?

选项:

A、Doctors who are general practitioners rather than orthopedists are less likely than orthopedists to judge the stability of an ankle frac-ture correctly.
B、Many ankle injuries for which an initial x-ray is ordered are revealed by the x-ray not to involve any fracture of the ankle.
C、X-rays of patients of many different orthopedists working in several hospitals were reviewed.
D、The healing of ankle fractures that have been surgically repaired is always checked by means of a follow-up x-ray.
E、Orthopedists routinely order follow-up x-rays for fractures of bone other than ankle bones.

答案:

C
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[Sentence Correction]

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题目：

Even though her career was cut short when she was in her prime and the fifteen recordings she made were disappointing artistically as well as technically, Olive Fremstad (1871-1951) has never been entirely forgotten by opera aficionados.

选项:

A、though her career was cut short when she was in her prime and the fifteen recordings she made were
B、though her career was cut short while in her prime, with the fifteen recordings she made
C、as her career had been cut short when she was in her prime, with the fifteen recordings she had made
D、with her career having been cut short when she was in her prime, and the fifteen recordings she made were
E、with her career cut short while in her prime, and that the fifteen recordings she made were

答案:

A
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[Sentence Correction]

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题目：

Humans have been damaging the environment for centuries by overcutting trees and farming too intensively, and though some protective measures, like the establishment of national forests and wildlife sanctuaries, having been taken decades ago, great increases in population and in the intensity of industrialization are causing a worldwide ecological crisis.

选项:

A、though some protective measures, like the establishment of national forests and wildlife sanctuaries, having been taken decades ago, great increases in population
B、though some protective measures, such as the establishment of national forests and wildlife sanctuaries, were taken decades ago, great increases in population
C、though some protective measures, such as establishing national forests and wildlife sanctuaries having been taken decades ago, great population increases
D、with some protective measures, like establishing national forests and wildlife sanctuaries that were taken decades ago, great increases in population
E、with some protective measures, such as the establishment of national forests and wildlife sanctuaries, having been taken decades ago, great population increases

答案:

B
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[Sentence Correction]

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题目：

The decline of the mountain yellow-legged frog in the high reaches of the Sierra Nevada has become severe enough for the United States Fish and Wildlife Service quite possibly to list it as an endangered species in the near future.
 

选项:

A、 severe enough for the United States Fish and Wildlife Service quite possibly to list it
B、 severe enough so that the United States Fish and Wildlife Service could well list them
C、 severe enough for it quite possibly to be listed by the United States Fish and Wildlife Service
D、 so severe that the United States Fish and Wildlife Service could well list it
E、 so severe that they could well be listed by the United States Fish and Wildlife Service

答案:

D
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[Sentence Correction]

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题目：

Although the rise in the Producer Price Index was greater than expected, most analysts agreed that the index was unlikely to continue going up and that inflation remained essentially under control.

选项:

A、that the index was unlikely to continue going up and that inflation remained
B、that it was unlikely for the index continuing to go up and for inflation to remain
C、that the index was unlikely to continue to go up, with inflation to remain
D、on the unlikelihood that the index would continue going up and that inflation remained
E、on the unlikelihood that the index would continue to go up and for inflation to remain

答案:

A
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[Data Sufficiency]

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题目：

$10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years is given by D(t) = 10,000 {1+(r/100)}t.  What amount will the deposit grow to in 3 years?
(1) D(1) = 11,000
(2) r =10

选项:

答案:

D
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[Problem Solving]

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题目：

Thabo owns exactly 140 books, and each book is either paperback fiction, paperback nonfiction, or hardcover nonfiction. If he owns 20 more paperback nonfiction books than hardcover nonfiction books, and twice as many paperback fiction books as paperback nonfiction books, how many hardcover nonfiction books does Thabo own?

选项:

A、10
B、20
C、30
D、40
E、50

答案:

B
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791浏览

[Undefined]

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Art historian: Unlike many artistic traditions that sought to depict plants native to the local area in a seasonally appropriate way (for example, depicting scenes of spring with the plants in the appropriate stages of development for that season), seventeenth-century Dutch artists specializing in flower paintings almost exclusively chose to depict exotic species of flowers from outside the local area. Painting such species was worthwhile primarily because the art-buying public had developed a strong preference for images of the exotic. The great botanical centers of the time gave the artists direct access to such flowers, which the artists would freely combine in a single painting, regardless of whether the combined species occurred together in the wild, and depicted each in full bloom, regardless of whether those species bloomed at the same time in nature.

Statement: The art historian makes the point that the species of flowers these Dutch artists chose to paint were 1 largely because the species were 2 .

Select for 1 and for 2 the options that complete the statement so that it is most strongly supported by the information provided. Make only two selections, one in each column.
我选的CE，和EC有什么区别？怎么选出EC的？
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2407浏览

[Undefined]

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An unusually severe winter occurred in Europe after the continent was blanketed by a blue haze resulting from the eruption of the Laki Volcano in the European republic of Iceland in the summer of 1984.  Thus, it is evident that major eruptions cause the atmosphere to become cooler than it would be otherwise.
Which of the following statements, if true, most seriously weakens the argument above?
C选项为什么就不会有张冠李戴的问题呢，1984和1982的气候情况能一样吗，C里的火山就可以试用于原文的火山吗
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2637浏览

[Undefined]

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The rate of a certain chemical reaction is directly proportional to the square of the concentration of chemical A present and inversely proportional to the concentration of chemical B present. If the concentration of chemical B is increased by 100 percent, which of the following is closest to the percent change in the concentration of chemical A required to keep the reaction rate unchanged?
为什么这个题一定是相乘不能是相加呢？y=k1A方-k2B （k1,k2大于0 ），也满足题目说的与A方成正比与B成反比啊？但是这道题只有相乘的情况才能选出正确答案
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923浏览

[Undefined]

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Tiger beetles are such fast runners that they can capture virtually any nonflying insect.  However, when running toward an insect, the beetles intermittently stop, and then, a moment later, resume their attack.  Perhaps they cannot maintain their pace and must pause for a moment's rest; but an alternative hypothesis is that while running tiger beetles are unable to process the resulting rapidly changing visual information, and so quickly go blind and stop.
 
Which of the following, if discovered in experiments using artificially moved prey insects, would support one of the two hypotheses and undermine the other?
答案C是怎么支持一个猜想又削弱另一个猜想的？
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2115浏览

[GWD]

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The author of the passage implies that which of the following is a possible partial explanation for acquisition behavior during the 1970's and 1980's?
请解释这道题为什么不选C或E，除了正确选项B，我认为文中也正确地提到了这两个选项可以解释acquisition behavior during 1970s and 80s
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1458浏览

[OG]

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The primary purpose of the passage is to
为什么选E不选B
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946浏览

[Undefined]

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Club X has more than 10 but fewer than 40 members. Sometimes the members sit at tables with 3 members at one table and 4 members at each of the other tables, and sometimes they sit at tables with 3 members at one table and 5 members at each of the other tables. If they sit at tables with 6 members at each table except one and fewer than 6 members at that one table, how many members will be at the table that has fewer than 6 members?
提问小梅老师 这道题求讲一下 我没什么思路 带入数字得的是3
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980浏览

[Undefined]

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A photography dealer ordered 60 Model X cameras to be sold for $250 each, which represents a 20 percent markup over the dealer's initial cost for each camera. Of the cameras ordered, 6 were never sold and were returned to the manufacturer for a refund of 50 percent of the dealer's initial cost. What was the dealer's approximate profit or loss as a percent of the dealer's initial cost for the 60 cameras?
请问小梅老师 这道题讲讲一下 我算的是19% 原来成本是200每个 亏了6个 每个亏100. 最后得不出答案
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230178浏览

[Undefined]

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Analytical!
请问may老师，这题该用什么思路来做？
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237302浏览

[Undefined]

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Analytical!
请问张老师，这道题为什么D不对？我有我觉得second paragraph最后一句话特别指向D
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