问答

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[Problem Solving]

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文章：

题目：

Pat will walk from Intersection X to Intersection Y along a route that is confined to the square grid of four streets and three avenues shown in the map above. How many routes from X to Y can Pat take that have the minimum possible length?

选项:

A、68
B、10
C、14
D、16

答案:

C
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[Reading Comprehension]

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文章：

Line        Conodonts, the spiky phosphatic remains (bones
 and teeth composed of calcium phosphate) of
 tiny marine animals that probably appeared about
 520 million years ago, were once among the most
(5)controversial of fossils. Both the nature of the
 organism to which the remains belonged and the
 function of the remains were unknown. However,
 since the 1981 discovery of fossils preserving not
 just the phosphatic elements but also other remains
(10)of the tiny soft-bodied animals (also called conodonts)
 that bore them, scientists' reconstructions of the
 animals' anatomy have had important implications
 for hypotheses concerning the development of the
 vertebrate skeleton.
(15)     The vertebrate skeleton had traditionally been
 regarded as a defensive development, champions of
 this view postulating that it was only with the much
 later evolution of jaws that vertebrates became
 predators. The first vertebrates, which were soft-
(20)bodied, would have been easy prey for numerous
 invertebrate carnivores, especially if these early
 vertebrates were sedentary suspension feeders.
 Thus, traditionalists argued, these animals developed
 coverings of bony scales or plates, and teeth were
(25)secondary features, adapted from the protective
 bony scales. Indeed, external skeletons of this
 type are common among the well-known fossils of
 ostracoderms, jawless vertebrates that existed from
 approximately 500 to 400 million years ago.
(30)However, other paleontologists argued that many of
 the definitive characteristics of vertebrates, such as
 paired eyes and muscular and skeletal adaptations
 for active life, would not have evolved unless the
(35)first vertebrates were predatory. Teeth were more
 primitive than external armor according to this view,
 and the earliest vertebrates were predators.
      The stiffening notochord along the back of the
 body, V-shaped muscle blocks along the sides,
(40)and posterior tail fins help to identify conodonts as
 among the most primitive of vertebrates. The lack of
 any mineralized structures apart from the elements
 in the mouth indicates that conodonts were more
 primitive than the armored jawless fishes such as the
(45)ostracoderms. It now appears that the hard parts that
 first evolved in the mouth of an animal improved its
 efficiency as a predator, and that aggression rather
 than protection was the driving force behind the origin
 of the vertebrate skeleton.

题目：

It can be inferred that on the basis of the 1981 discovery of conodont remains, paleontologists could draw which of the following conclusions?

选项:

答案:

B
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题目：

Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.

选项:

A、Over the course of the eighteenth century, the average output of ironwork tripled as a result of several improvements in blowing machinery and because coal replaced charcoal as the fuel used in the smelting of iron ore.
B、Over the course of the eighteenth century a tripling in the average output of ironwork was due to the replacement of charcoal by coal for the fuel used in the smelting of iron ore, in addition to several improvements in blowing machinery.
C、With charcoal's being replaced by coal as the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.
D、The replacement of charcoal with coal for the fuel used in the smelting of iron ore and several improvements in blowing machinery, the average output of ironwork tripled over the eighteenth century.
E、Charcoal being replaced by coal as the fuel used in the smelting of iron ore, and several improvements in blowing machinery, which tripled the average output of ironwork over the course of the eighteenth century.

答案:

A
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[Critical Reasoning]

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题目：

Unless tiger hunting decreases, tigers will soon be extinct in the wild.  The countries in which the tigers' habitats are located are currently debating joint legislation that would ban tiger hunting.  Thus, if these countries can successfully enforce this legislation, the survival of tigers in the wild will be ensured.
 
The reasoning in the argument is most vulnerable to criticism on the grounds that the argument

选项:

A、assumes without sufficient warrant that a ban on tiger hunting could be successfully enforced
B、considers the effects of hunting on tigers without also considering the effects of hunting on other endangered animal species
C、fails to take into account how often tiger hunters are unsuccessful in their attempts to kill tigers
D、neglects to consider the results of governmental attempts in the past to limit tiger hunting
E、takes the removal of an impediment to the tigers' survival as a guarantee of their survival

答案:

E
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题目：

There are hopeful signs that we are shifting away from our heavy reliance on fossil fuels:  more than ten times as much energy is generated through wind power now than it was in 1990.

选项:

A、generated through wind power now than it was
B、generated through wind power now as it was
C、generated through wind power now as was the case
D、now generated through wind power as it was
E、now generated through wind power than was the case

答案:

C
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[Problem Solving]

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题目：

Box W and Box V each contain several blue sticks and red sticks, and all of the red sticks have the same length. The length of each red stick is 18 inches less than the average length of the sticks in Box W and 6 inches greater than the average length of the sticks in Box V.  What is the average (arithmetic mean) length, in inches, of the sticks in Box W minus the average length, in inches, of the sticks in Box V?

选项:

A、3
B、6
C、12
D、18
E、24

答案:

E
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题目：

To map Earth's interior, geologists use a network of seismometers to chart seismic waves that originate in the earth's crust and ricochet around its interior, most rapidly traveling through cold, dense regions and slower through hotter rocks.

选项:

A、interior, most rapidly traveling through cold, dense regions and slower
B、interior, which travel most rapidly through cold, dense regions, and more slowly
C、interior, traveling most rapidly through cold, dense regions and more slowly
D、interior and most rapidly travel through cold, dense regions, and slower
E、interior and that travel most rapidly through cold, dense regions and slower

答案:

C
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[Reading Comprehension]

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文章：

    Diamonds are almost impossible to detect directly because they are so rare: very rich kimberlite pipes, the routes through which diamonds rise, may contain only three carats of diamonds per ton of kimberlite. Kimberlite begins as magma in Earth's mantle (the layer between the crust and the core). As the magma smashes through layers of rock, it rips out debris, creating a mix of liquid and solid material. Some of the solid material it brings up may come from a so-called diamond-stability field, where conditions of pressure and temperature are conducive to the formation of diamonds. If diamonds are to survive, though, they must shoot toward Earth's surface quickly. Otherwise, they revert to graphite or burn. Explorers seeking diamonds look for specks of "indicator minerals" peculiar to the mantle but carried up in greater quantities than diamonds and eroded out of kimberlite pipes into the surrounding land. The standard ones are garnets, chromites, and ilmenites. One can spend years searching for indicators and tracing them back to the pipes that are their source; however, 90 percent of kimberlite pipes found this way are barren of diamonds, and the rest are usually too sparse to mine.

    In the 1970's the process of locating profitable pipes was refined by focusing on the subtle differences between the chemical signatures of indicator minerals found in diamond-rich pipes as opposed to those found in barren pipes. For example, G10 garnets, a type of garnet typically found in diamond-rich pipes, are lower in calcium and higher in chrome than garnets from barren pipes. Geo-chemists John Gurney showed that garnets with this composition were formed only in the diamond-stability field; more commonly found versions came from elsewhere in the mantle. Gurney also found that though ilmenites did not form in the diamond-stability field, there was a link useful for prospectors: when the iron in ilmenite was highly oxidized, its source pipe rarely contained any diamonds. He reasoned that iron took on more or less oxygen in response to conditions in the kimberlitic magma itself—mainly in response to heat and the available oxygen. When iron became highly oxidized, so did diamonds; that is, they vaporized into carbon dioxide.

题目：

The primary purpose of the passage is to

选项:

A、discuss an objection to Gurney's theories about the uses of indicator minerals
B、explore the formation of diamonds and the reasons for their scarcity
C、analyze the importance of kimberlite pipes in the formation of diamonds
D、define the characteristics of indicator minerals under differing conditions
E、explain a method of determining whether kimberlite pipes are likely to contain diamonds

答案:

E
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[Critical Reasoning]

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题目：

In a study conducted in Pennsylvania, servers in various restaurants wrote "Thank you" on randomly selected bills before presenting the bills to their customers.  Tips on these bills were an average of three percentage points higher than tips on bills without the message.  Therefore, if servers in Pennsylvania regularly wrote "Thank you" on restaurant bills, their average income from tips would be significantly higher than it otherwise would have been.
 
Which of the following is an assumption on which the argument relies?

选项:

A、The 'Thank you' messages would have the same impact on regular patrons of a restaurant as they would on occasional patrons of the same restaurant.
B、Regularly seeing 'Thank you' written on their bills would not lead restaurant patrons to revert to their earlier tipping habits.
C、The written 'Thank you' reminds restaurant patrons that tips constitute a significant part of the income of many food servers.
D、The rate at which people tip food servers in Pennsylvania does not vary with how expensive a restaurant is.
E、Virtually all patrons of the Pennsylvania restaurants in the study who were given a bill with 'Thank you' written on it left a larger tip than they otherwise would have.

答案:

B
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题目：

At the annual stockholders meeting, investors heard a presentation on the numerous challenges facing the company, including among them the threat from a rival's multibillion-dollar patent-infringement suit and the declining sales for the company's powerful microprocessor chip.

选项:

A、including among them the threat from a rival's multibillion-dollar patent-infringement suit and the declining sales for
B、which includes the threat of a rival's multibillion-dollar patent-infringement suit and declining sales of
C、included among these the threat from a rival's multibillion-dollar patent-infringement suit as well as a decline in sales for
D、among them the threat of a rival's multibillion-dollar patent-infringement suit and the decline in sales of
E、among these the threat from a rival's multibillion-dollar patent-infringement suit as well as the decline in sales for

答案:

D
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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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