问答

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[Reading Comprehension]

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文章：

A recent study has provided clues to predator-prey dynamics in the late Pleistocene era.  Researchers compared the number of tooth fractures in present-day carnivores with tooth fractures in carnivores that lived 36,000 to 10,000 years ago and that were preserved in the Rancho La Brea tar pits in Los Angeles.  The breakage frequencies in the extinct species were strikingly higher than those in the present-day species.
 
In considering possible explanations for this finding, the researchers dismissed demographic bias because older individuals were not overrepresented in the fossil samples.  They rejected preservational bias because a total absence of breakage in two extinct species demonstrated that the fractures were not the result of abrasion within the pits.  They ruled out local bias because breakage data obtained from other Pleistocene sites were similar to the La Brea data.  The explanation they consider most plausible is behavioral differences between extinct and present-day carnivores--in particular, more contact between the teeth of predators and the bones of prey due to more thorough consumption of carcasses by the extinct species.  Such thorough carcass consumption implies to the researchers either that prey availability was low, at least seasonally, or that there was intense competition over kills and a high rate of carcass theft due to relatively high predator densities.

题目：

The primary purpose of the passage is to

选项:

A、present several explanations for a well-known fact
B、suggest alternative methods for resolving a debate
C、argue in favor of a controversial theory
D、question the methodology used in a study
E、discuss the implications of a research finding

答案:

E
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[Sentence Correction]

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题目：

A South American bird that forages for winged termites and other small insects while swinging upside down form the foliage of tall trees, the graveteiro belongs to the ovenbird family, a group of New World tropical birds that includes more than 230 species and that are represented in virtually every kind of habitat.

选项:

A、graveteiro belongs to the ovenbird family, a group of New World tropical birds that includes more than 230 species and that are
B、graveteiro belongs to the ovenbird family, a group of New World tropical birds that includes more than 230 species and  is
C、graveteiro belongs to the ovenbird family, a group of New World tropical birds that include more than 230 species and  is
D、graveteiro, which belongs to the ovenbird family, a group of New World tropical birds that includes more than 230 species and that are
E、graveteiro, which belongs to the ovenbird family, a group of New World tropical birds that includes more than 230 species and is

答案:

B
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[Sentence Correction]

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题目：

In 1713, Alexander Pope began his translation of the Iliad, a work that, taking him seven years until completion, and that literary critic Samuel Johnson, Pope's contemporary, pronounced the greatest translation in any language.

选项:

A、his translation of the Iliad, a work that, taking him seven years until completion, and that literary critic Samuel Johnson, Pope's contemporary, pronounced
B、his translation of the Iliad, a work that took him seven years to complete and that literary critic Samuel Johnson, Pope's contemporary, pronounced
C、his translation of the Iliad, a work that had taken seven years to complete and that literary critic Samuel Johnson, Pope's contemporary, pronounced it as
D、translating the Iliad, a work that took seven years until completion and that literary critic Samuel Johnson, Pope's contemporary, pronounced it as
E、translating the Iliad, a work that had taken seven years to complete and literary critic Samuel Johnson, Pope's contemporary, pronounced it

答案:

B
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[Sentence Correction]

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题目：

Since 1990 the global economy has grown more than it did during the 10,000 years from the beginning of agriculture to 1950.

选项:

A、Since 1990 the global economy has grown more than it did during the 10,000 years from the beginning of agriculture
B、Since 1990 the growth of the global economy has been more than that during 10,000 years, from when agriculture began
C、The growth of the global economy since 1990 exceeds that which had been for 10,000 years from the beginning of agriculture
D、The growth of the global economy since 1990 exceeds what it has been for 10,000 years, from when agriculture began
E、The growth of the global economy since 1990 exceeds what it did for the 10,000 years from the beginning of agriculture

答案:

A
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[Problem Solving]

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题目：

The letters D, G, I, I, and T can be used to form 5-letter strings such as DIGIT or DGIIT. Using these letters, how many 5-letter strings can be formed in which the two occurrences of the letter I are separated by at least one other letter?

选项:

A、12
B、18
C、24
D、36
E、48

答案:

D
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[Problem Solving]

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题目：

选项:
A、
B、
C、3
D、6
E、

答案:

C
4答疑

[Reading Comprehension]

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文章：

    The idea that equipping homes with electrical appliances and other "modern" household technologies would eliminate drudgery, save labor time, and increase leisure for women who were full-time home workers remained largely unchallenged until the women's movement of the 1970's spawned the groundbreaking and influential works of sociologist Joann Vanek and historian Ruth Cowan. Vanek analyzed 40 years of timeuse surveys conducted by home economists to argue that electrical appliances and other modern household technologies reduced the effort required to perform specific tasks, but ownership of these appliances did not correlate with less time spent on housework by full-time home workers. In fact, time spent by these workers remained remarkably constant―at about 52 to 54 hours per week―from the 1920's to the 1960's, a period of significant change in household technology. In surveying two centuries of household technology in the United States, Cowan argued that the "industrialization" of the home often resulted in more work for full-time home workers because the use of such devices as coal stoves, water pumps, and vacuum cleaners tended to reduce the workload of married-women's helpers (husbands, sons, daughters, and servants) while promoting a more rigorous standard of housework. The full-time home worker's duties also shifted to include more household management, child care, and the post-Second World War phenomenon of being "Mom's taxi."

题目：

According to the passage, which of the following is true about the idea mentioned in the highlighted text?

选项:

A、It has been undermined by data found in time-use surveys conducted by home economists.
B、It was based on a definition of housework that was explicitly rejected by Vanek and Cowan.
C、It is more valid for the time period studied by Cowan than for the time period studied by Vanek.
D、It is based on an underestimation of the time that married women spent on housework prior to the industrialization of the household.
E、It inaccurately suggested that new household technologies would reduce the effort required to perform housework.

答案:

A
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[Critical Reasoning]

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题目：

The cause of the wreck of the ship Edmund Fitzgerald in a severe storm on lake Superior is still unknown , when the sunken wreckage of the vessel was round , searchers discovered the hull in two pieces lying close together , The storm's violent waves would have caused separate pieces floating even briefly on the surface to drift apart . Therefore . the breakup of the null can be ruled out as the cause of the sinking .
 
Which of the following is an assumption on which the argument depends?

选项:

A、Ships as large as the Edmund Fitzgerald rarely sink except in the most violent weather.
B、Under water currents at the time of the storm did not move the sepa-rated pieces of the hull together again .
C、Pieces of the hull would have sunk more quickly than the intact hull would have
D、The waves of the storm were not violent enough to have caused the
E、If the ship broke up before sinking , the pieces of the hull would not have remained on the surface for very long

答案:

B
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[Critical Reasoning]

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题目：

Scientists are discussing ways to remove excess carbon dioxide from the atmosphere by increasing the amount that is absorbed by plant life.  One plan to accomplish this is to establish giant floating seaweed farms in the oceans.  When the seaweed plants die, they will be disposed of by being burned for fuel.
 
Which of the following, if true, would indicate the most serious weakness in the plan above?

选项:

A、Some areas of ocean in the Southern Hemisphere do not contain sufficient nutrients to support large seaweed farms.
B、When a seaweed plant is burned, it releases an amount of carbon dioxide comparable to the amount it has absorbed in its lifetime.
C、Even if seaweed farms prove effective, some people will be reluctant to switch to this new fuel.
D、Each year about seven billion tons of carbon dioxide are released into the atmosphere but only about five billion tons are absorbed by plant life.
E、Seaweed farms would make more money by farming seaweed to sell as nutritional supplements than by farming seaweed to sell as fuel.

答案:

B
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[Problem Solving]

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题目：

Last year the price per share of Stock X increased by k percent and the earnings per share of Stock X increased by m percent, where k is greater than m.  By what percent did the ratio of price per share to earnings per share increase, in terms of k and m?

选项:

A、k/m %
B、(k-m) %
C、[100(k-m)]/(100+k) %
D、[100(k-m)]/(100+m) %
E、[100(k-m)]/(100+k+m) %

答案:

D
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1284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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3627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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4004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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1333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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2989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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2070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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1330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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1398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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330278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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337404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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