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题目：

In 1926, in her second attempt to swim across the English Channel,
Gertrude Ederle not only crossed the Channel against currents that
Forced her to swim thirty-five miles instead of the minimal twenty-one,
but she set a record for speed as well, by swimming the distance in
almost two hours faster than anyone had yet done.

选项:

A、but she set a record for speed as well, by swimming the dis-tance in almost two hours faster than anyone had yet done.
B、but also set a record for speed, swimming the distance almost two hours faster than anyone had yet done.
C、but also swam the distance in almost two hours faster than any-anyone had yet done, and setting a record for speed
D、but also setting a record for speed by swimming the distance in almost two hours faster than anyone had yet done.
E、but, swimming the distance almost two hours faster than anyone had yet done, she also set a record for speed.

答案:

B
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题目：

Carbon-14 dating reveals that the megalithic monuments in Brittany are nearly 2,000 years as old as any of their supposed Mediterranean predecessors.

选项:

A、as old as any of their supposedolder than any of their supposed
B、as old as their supposed
C、older than any of their supposedly
D、as old as their supposedly

答案:

B
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[Critical Reasoning]

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题目：

In Berinia, the age at which people could begin to drink alcohol legally used to be 18.  In 1990, in an attempt to reduce alcohol consumption and thereby to reduce alcohol-related traffic deaths among Berinians under 21, the legal drinking age was raised to 21.  Alcohol-related traffic deaths among people under 21 have decreased significantly since 1990.  Nevertheless, surveys show that people in that age-group drink just as much alcohol as they did before 1990.
 
Which of the following, if true of Berinia, most helps to resolve the apparent discrepancy?

选项:

A、For the population as a whole, annual alcohol consumption is no lower now than it was in 1990.
B、Alcohol consumption away from home, for example in bars and restaurants, is much lower among people under 21 than it was in 1990.
C、The proportion of people under 21 who own a car is higher now than it was in 1990.
D、Alcohol consumption is lower among people under 21 than among adults in most other age-groups.
E、Alcohol-related traffic deaths among people over 21 have increased slightly since 1990.

答案:

B
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题目：

 What is the perimeter of Triangle ABC in the figure below?
 

选项:

A、A
B、B
C、C
D、D
E、E

答案:

B
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[Critical Reasoning]

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题目：

Personnel officer:  The exorbitant cost of our health-insurance benefits reflects the high dollar amount of medical expenses incurred by our employees.  Employees who are out of shape, as a group, have higher doctor bills and longer hospital stays than do their colleagues who are fit.  Therefore, since we must reduce our health-insurance costs, we should offer a rigorous fitness program of jogging and weight lifting to all employees, and require employees who are out of shape to participate.
 
The conclusion reached by the personnel officer depends on which of the following assumptions?

选项:

A、A person who is fit would receive a routine physical checkup by a doctor less regularly than would a person who is out of shape.
B、The medical expenses incurred by employees who are required to participate in the fitness program would be less than those incurred by employees who are not required to participate.
C、The strenuous activities required of out-of-shape employees by the program would not by themselves generate medical expenses greater than any reduction achieved by the program.
D、The fitness program would serve more employees who are out of shape than it would employees who are fit.
E、The employees who participate in the fitness program would be away from work because of illness less than would the employees who do not participate.

答案:

C
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题目：

For any integer k greater than 1, the symbol  denotes the product of all the fractions of the form , where t is an integer between 1 and k , inclusive. What is the value of ?

选项:

A、5
B、5/4
C、4/5
D、1/4
E、1/5

答案:

E
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题目：

First discovered more than 30 years ago, Lina's sunbird, a four-and-a-half-inch animal found in the Philippines and that resembles a hummingbird, has shimmering metallic colors on its head; a brilliant orange patch, bordered with red tufts, in the center of its breast; and a red eye.

选项:

A、 found in the Philippines and that resembles
B、 found in the Philippines and that, resembling
C、 found in the Philippines and resembling
D、 that is found in the Philippines and it resembles
E、 that is found in the Philippines and that, resembling

答案:

C
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[Reading Comprehension]

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文章：

    In most earthquakes the Earth's crust cracks like porcelain, Stress builds up until a fracture forms at a line depth of a few kilometers and the crust slips to relieve the stress. Some earthquakes, however, take place hun dreds of kilometers down in the Earth's mantle, where high pressure makes rock so ductile that it flows instead of cracking, even under stress severe enough to deform it like putty. How can there be earthquakes at such depths?

    That such deep events do occur has been accepted only since 1927. when the seismologist Kiyoo Wadati convincingly demonstrated their existence. Instead of comparing the arrival times of seismic waves at different locations, as earlier researchers had done, Wadati relied on a time difference between the arrival of primary(P) waves and the slower secondary(S) waves. Because P and S waves travel at different but fairly constant speeds, the interval between their arrivals increases in proportion to the distance from the earthquake focus, or initial rupture point.

    For most earthquakes, wadati discovered, the interval was quite short near the epicenter; the point on the surface where shaking is strongest. For a few events, however, the delay was long even at the epicenter. Wadati saw a similar pattern when he analyzed data on the intensity of shaking. Most earthquakes had a small area of intense shaking, which weakened rapidly with increasing distance from the epicenter. but others were characterized by a lower peak intensity, felt over a broader area. Both the P-S intervals and the intensity patterns suggested two kinds of earthquakes: the more common shallow events, in which the focus lay just under the epicenter, and deep events, with a focus several hundred kilometers down.

    The question remained: how can such quakes occur, given that mantle rock at a depth of more than 50 kilometers is too ductile to store enough stress to fracture? Wadati's work suggested that deep events occur in areas (now called Wadati-Benioff zones) where one crustal plate is forced under another and descends into the mantle. The descending rock is substantially cooler than the surrounding mantle and(60) hence is less ductile and much more liable to fracture.

题目：

information presented in the passage sug-gests that, compared with seismic activity at the epicenter of a shallow event, seismic activity at the epicenter of a deep event is characterized by

选项:

A、shorter P-S intervals and higher peak intensity
B、shorter P-S intervals and lower peak intensity
C、longer P-S intervals and similar peak intensity
D、longer P-S intervals and higher peak intensity
E、longer P-S intervals and lower peak intensity.

答案:

E
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题目：

If f is the function defined by f(x) = x2 (1-x)2 for all x, then f(1-x) =

选项:

A、f(x)
B、[f(x)]2
C、1 - f(x)
D、(1-x) f(x)
E、f(1) - f(x)

答案:

A
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文章：

Line         A small number of the forest species of
  lepidoptera (moths and butterflies, which exist as
  caterpillars during most of their life cycle) exhibit
  regularly recurring patterns of population growth
(5) and decline—such fluctuations in population are
  known as population cycles. Although many different
  variables influence population levels, a regular pattern
  such as a population cycle seems to imply a
  dominant, driving force. Identification of that driving
(10) force, however, has proved surprisingly elusive
  despite considerable research. The common
  approach of studying causes of population cycles by
  measuring the mortality caused by different agents,
  such as predatory birds or parasites, has been
(15) unproductive in the case of lepidoptera. Moreover,
  population ecologists’ attempts to alter cycles by
  changing the caterpillars’ habitat and by reducing
  caterpillar populations have not succeeded. In short,
  the evidence implies that these insect populations, if
(20) not self-regulating, may at least be regulated by an
  agent more intimately connected with the insect than
  are predatory birds or parasites.
       Recent work suggests that this agent may be a
  virus. For many years, viral disease had been reported
(25) in declining populations of caterpillars, but population
  ecologists had usually considered viral disease to
  have contributed to the decline once it was underway
  rather than to have initiated it. The recent work has
  been made possible by new techniques of molecular
(30) biology that allow viral DNA to be detected at low
  concentrations in the environment. Nuclear
  polyhedrosis viruses are hypothesized to be the
  driving force behind population cycles in lepidoptera
  in part because the viruses themselves follow an
(35) infectious cycle in which, if protected from direct
  sun light, they may remain virulent for many years
  in the environment, embedded in durable crystals of
  polyhedrin protein. Once ingested by a caterpillar,
  the crystals dissolve, releasing the virus to infect
(40) the insect’s cells. Late in the course of the infection,
  millions of new virus particles are formed and
  enclosed in polyhedrin crystals. These crystals
  reenter the environment after the insect dies and
  decomposes, thus becoming available to infect
(45) other caterpillars.
       One of the attractions of this hypothesis is its broad
  applicability. Remarkably, despite significant differences
  in habitat and behavior, many species of lepidoptera
  have population cycles of similar length, between eight
(50) and eleven years. Nuclear polyhedrosis viral infection is
  one factor these disparate species share.


题目：

It can be inferred from the passage that while inside its polyhedrin protein crystals, the nuclear polyhedrosis virus

选项:

A、is exposed to direct sunlight
B、is attractive to predators
C、cannot infect caterpillars’ cells
D、cannot be ingested by caterpillars
E、cannot be detected by new techniques of molecular biology

答案:

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