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题目：

Mixed with an equal part of water, ethylene glycol, a compound commonly used as automotive an antifreeze, is effective at temperatures as low as -30 degrees Fahrenheit.

选项:

A、temperatures as low
B、temperatures so low 
C、as low temperatures 
D、as few 
E、as little

答案:

A
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[Reading Comprehension]

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文章：

Line        In the Sonoran Desert of northwestern Mexico and
 southern Arizona, the flowers of several species of
 columnar cacti—cardon, saguaro, and organ
 pipe—were once exclusively pollinated at night by
(5)nectar-feeding bats, as their close relatives in arid
 tropical regions of southern Mexico still are. In these
 tropical regions, diurnal (daytime) visitors to columnar
 cactus flowers are ineffective pollinators because,
 by sunrise, the flowers' stigmas become unreceptive
(10)or the flowers close. Yet the flowers of the Sonoran
 Desert cacti have evolved to remain open after sunrise,
 allowing pollination by such diurnal visitors as bees and
 birds. Why have these cacti expanded their range of
 pollinators by remaining open and receptive in daylight?
(15)     This development at the northernmost range of
 columnar cacti may be due to a yearly variation in the
 abundance—and hence the reliability—of migratory
 nectar-feeding bats. Pollinators can be unreliable
 for several reasons. They can be dietary generalists
(20)whose fidelity to a particular species depends on
 the availability of alternative food sources. Or, they
 can be dietary specialists, but their abundance may
 vary widely from year to year, resulting in variable
 pollination of their preferred food species. Finally, they
(25)may be dietary specialists, but their abundance may
 be chronically low relative to the availability of flowers.
      Recent data reveals that during spring in the
 Sonoran Desert, the nectar-feeding bats are
 specialists feeding on cardon, saguaro, and
(30)organpipe flowers. However, whereas cactus-flower
 abundance tends to be high during spring, bat
 population densities tend to be low except near
 maternity roosts. Moreover, in spring, diurnal cactus-
 pollinating birds are significantly more abundant in
(35)this region than are the nocturnal bats. Thus, with bats
 being unreliable cactus-flower pollinators, and daytime
 pollinators more abundant and therefore more reliable,
 selection favors the cactus flowers with traits that
 increase their range of pollinators. While data suggest
(40)that population densities of nectar-feeding bats are
 also low in tropical areas of southern Mexico, where
 bats are the exclusive pollinators of many species
 of columnar cacti, cactus-flower density and bat
 population density appear to be much more evenly
(45)balanced there: compared with the Sonoran Desert's
 cardon and saguaro, columnar cacti in southern Mexico
 produce far fewer flowers per night. Accordingly,
 despite their low population density, bats are able to
 pollinate nearly 100 percent of the available flowers.

题目：

The primary purpose of the passage is to

选项:

A、has not significantly reduced the gaps existing
B、has not been significant in reducing the gap that exists
C、has not made a significant reduction in the gap that exists
D、have not significantly reduced the gap that exists
E、have not been significant in a reduction of the gaps existing

答案:

C
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题目：

Positing an enormous volcanic explosion at the end of the Permian period would explain the presence of a buried crater, account for the presence of the element iridium (originating deep within the earth), and the presence of quartz having been shattered by high-impact shock waves.

选项:

答案:

B
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题目：

A recent review of pay scales indicates that CEO's now earn an average of 419 times more pay than blue-collar workers, compared to a ratio of 42 times in 1980.

选项:

A、that CEO's now earn an average of 419 times more pay than blue-collar workers, compared to a ratio of 42 times
B、that, on average, CEO's now earn 419 times the pay of blue-collar workers, a ratio that compares to 42 times
C、that, on average, CEO's now earn 419 times the pay of blue-collar workers, as compared to 42 times their pay, the ratio
D、CEO's who now earn on average 419 times more pay than blue-collar workers, as compared to 42 times their pay, the ratio
E、CEO's now earning an average of 419 times the pay of blue-collar workers, compared to the ratio of 42 times

答案:

C
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题目：

In many of the world's regions, increasing pressure on water resources has resulted both from expanding development, changes in climate, and from pollution, so that the future supply in some of the more arid areas is a concern going forward.

选项:

答案:

D
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题目：

Consumers may not think of household cleaning products to be hazardous substances, but many of them can be harmful to health, especially if they are used improperly.

选项:

A、Consumers may not think of household cleaning products to beConsumers may not think of household cleaning products being
B、A consumer may not think of their household cleaning products being
C、A consumer may not think of household cleaning products as
D、Household cleaning products may not be thought of by consumers, as

答案:

D
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题目：

Sound can travel through water for enormous distances, prevented from dissipating its acoustic energy as a result of boundaries in the ocean created by water layers of different temperatures and densities.

选项:

答案:

C
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题目：

Thomas Eakins' powerful style and his choices of subject—the advances in modern surgery, the discipline of sport, the strains of individuals in tension with society or even with themselves—was as disturbing to his own time as it is compelling for ours.

选项:

答案:

B
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文章：

题目：

The author of the passage would be most likely to agree with which of the following statements about the Milankovitch theory?

选项:

A、It is the only possible explanation for the ice ages.
B、It is too limited to provide a plausible explanation for the ice ages, despite recent research findings.
C、It cannot be tested and confirmed until further research on volcanic activity is done.
D、It is one plausible explanation, though not the only one, for the ice ages.
E、It is not a plausible explanation for the ice ages, although it has opened up promising possibilities for future research.

答案:

D
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题目：

Which of the following best describes the relationship of the second paragraph to the first paragraph?

选项:

A、 It presents contrasting explanations for a phenomenon presented in the first paragraph.
B、 It discusses an exception to a general principle outlined in the first paragraph.
C、 It provides information that qualifies a claim presented in the first paragraph.
D、 It presents an example that strengthens a claim presented in the first paragraph.
E、 It presents an alternative approach to solving a problem discussed in the first paragraph.

答案:

C
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1312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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3703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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4095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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1354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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3049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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2105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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1349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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1424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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335780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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342906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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