[Problem Solving]
试题详情
题目：
If M is the least common multiple of 90, 196, and 300, which of the following is NOT a factor of M?
选项:
A、600
B、 700
C、900
D、2,100
E、4,900
答案:
A
问答
3答疑
3答疑
[Sentence Correction]
试题详情
题目：
1998 saw several new ventures promoting online distance learning both at the college and graduate level, but also faculty members in large numbers began questioning whether the computer screen was an adequate replacement for the classroom.
选项:
A、 1998 saw several new ventures promoting online distance learning both at the college and graduate level, but also faculty members in large numbers began
B、 In 1998 several new ventures were promoting online distance learning for both college-and for graduate-level courses, but it was also a year for a large number of faculty members who began
C、 With several new ventures promoting online distance learning both for college and graduate courses in 1998, it was also a year when a large number of faculty members had begun
D、 Although 1998 saw several new ventures promoting online distance learning for both college- and graduate-level courses, it was also a year when a large number of faculty members began
E、 Several new ventures were promoting online distance learning in 1998, at both the college level as well as the graduate, but it was also a year for faculty members to begin in large numbers
答案:
D
3答疑
[Sentence Correction]
试题详情
题目：
According to scholars, the earliest writing was probably not a direct rendering of speech, but was more likely to begin as a separate and distinct symbolic system of communication, and only later merged with spoken language.
选项:
A、was more likely to begin as
B、more than likely began as
C、more than likely beginning from
D、it was more than likely begun from
E、it was more likely that it began
答案:
B
3答疑
[Sentence Correction]
试题详情
题目：
Rivaling the pyramids of Egypt or even the ancient cities of the Maya as an achievement, the army of terra-cotta warriors created to protect Qin Shi Huang, China's first emperor, in his afterlife is more than 2,000 years old and took 700,000 artisans more than 36 years to complete them.
选项:
A、took 700,000 artisans more than 36 years to complete them
B、took 700,000 artisans more than 36 years to complete it
C、took 700,000 artisans more than 36 years to complete
D、700,000 artisans took more than 36 years to complete
E、to complete them took 700,000 artisans more than 36 years
答案:
C
3答疑
[Sentence Correction]
试题详情
题目：
Often incorrectly referred to as a tidal wave, a tsunami, a seismic sea wave that can reach up to 150 miles per hour in speed and 200 feet high, is caused by underwater earthquakes or volcanic eruptions.
选项:
A、up to 150 miles per hour in speed and 200 feet high, is
B、up to 150 miles per hour in speed and heights of up to 200 feet, is
C、speeds of up to 150 miles per hour and 200 feet high, are
D、speeds of up to 150 miles per hour and heights of up to 200 feet, is
E、speeds of up to 150 miles per hour and as high as 200 feet, are
答案:
D
3答疑
[Critical Reasoning]
试题详情
题目：
Mayor: Migrating shorebirds stop at our beach just to feed on horseshoe-crab eggs, a phenomenon that attracts tourists. To bring more tourists, the town council plans to undertake a beach reclamation project to double the area available to crabs for nesting.
Birdwatcher: Without a high density of crabs on a beach, migrating shorebirds will go hungry because shorebirds only eat eggs that a crab happens to uncover when it is digging its own nest.
Which of the following, if true, would provide the mayor with the strongest counter to the birdwatcher's objection?
选项:
A、Every year a certain percentage of crabs are caught by fishermen as bait for eel traps.
B、Horseshoe crabs are so prolific that given favorable circumstances their numbers increase rapidly.
C、On average, tourists who come to the town in order to watch birds spend more money there than tourists who come for other purposes.
D、The additional land made available by the reclamation project will give migrating shorebirds more space.
E、Some of the migrating shorebirds make only one stop during their migration form South America to Canada.
答案:
B
3答疑
[Critical Reasoning]
试题详情
题目：
Over the past five years, the price gap between name-brand cereals and less expensive store-brand cereals has become so wide that consumers have been switching increasingly to store brands despite the name brands' reputation for better quality. To attract these consumers back, several manufacturers of name-brand cereals plan to narrow the price gap between their cereals and store brands to less than what it was five years ago.
Which of the following, if true, most seriously calls into question the likelihood that the manufacturers' plan will succeed in attracting back a large percentage of consumers who have switched to store brands?
选项:
A、There is no significant difference among manufacturers of name-brand cereals in the prices they charge for their products.
B、Consumers who have switched to store-brand cereals have generally been satisfied with the quality of those cereals.
C、Many consumers would never think of switching to store-brand cereals because they believe the name brand cereals to be of better quality.
D、Because of lower advertising costs, stores are able to offer their own brands of cereals at significantly lower prices than those charged for name-brand cereals.
E、Total annual sales of cereals-including both name-brand and store-brand cereals-have not increased significantly over the past five years.
答案:
B
3答疑
[Reading Comprehension]
试题详情
文章：
The term "episodic memory" was introduced by Tulving to refer to what he considered a uniquely human capacity-the ability to recollect specific past events, to travel back into the past in one's own mind-as distinct from the capacity simply to use information acquired through past experiences. Subsequently, Clayton et al. developed criteria to test for episodic memory in animals. According to these criteria, episodic memories are not of individual bits of information; they involvemultiple components of a single event "bound" together. Clayton sought to examine evidence of scrub jays' accurate memory of "what," "where," and "when" information and their binding of this information. In the wild, these birds store food for retrieval later during periods of food scarcity. Clayton's experiment required jays to remember the type, location, and freshness of stored food based on a unique learning event. Crickets were stored in one location and peanuts in another. Jays prefer crickets, but crickets degrade more quickly. Clayton's birds switched their preference from crickets to peanuts once the food had been stored for a certain length of time, showing that they retain information about the what, the where, and the when. Such experiments cannot, however, reveal whether the birds were reexperiencing the past when retrieving the information. Clayton acknowledged this by using the term "episodic-like" memory.
题目：
In order for Clayton's experiment to show that scrub jays have episodic-like memory, which of the following must be true in the experiment?
选项:
A、Some of the jays retrieved stored peanuts on the first occasion they were allowed to retrieve food.
B、All the crickets were retrieved before any of the peanuts were.
C、The peanuts were stored further away than the crickets.
D、When a jay attempted to retrieve a cricket or a peanut, the jay was prevented from eating it.
E、Throughout the experiment the jays were fed at levels typical of a time of scarcity.
答案:
E
3答疑
[Critical Reasoning]
试题详情
题目：
In order to raise revenue, the federal government planned a tax amnesty program that allows tax delinquents to pay all owed tax without added financial penalty. However, economists projected that the federal government would collect a far lower percentage of total tax owed by delinquents than did state governments implementing similar programs.
Which of the following, if true, would most contribute to an explanation of the economists' projections?
选项:
A、Tax amnesty programs are only successful if they are widely publicized.
B、Most people who honestly pay their state tax are equally honest in paying their federal tax.
C、Although federal tax delinquents usually must pay high financial penalties, the states require far lower financial penalties.
D、The state tax rate varies considerably from state to state, but the federal tax is levied according to laws which apply to citizens of all the states.
E、Unlike most federal tax delinquents, most state tax delinquents fail to pay state tax because of an oversight rather than a decision not to pay.
答案:
E
3答疑
[Reading Comprehension]
试题详情
文章：
Astronomers theorize that a black hole forms when a massive object shrinks catastrophically under its own gravity, leaving only a gravitational field so strong that nothing escapes it. Astronomers must infer the existence of black holes, which are invisible, from their gravitational influence on the visible bodies surrounding them. For example, observations indicate that gas clouds in galaxy M87 are whirling unusually fast about the galaxy's center. Most astronomers believe that the large concentration of mass at the galaxy's center is a black hole whose gravity is causing the gas to whirl. A few skeptics have argued that the concentration of mass necessary to explain the speed of the whirling gas is not necessarily a black hole: the concentration in M87 might be a cluster of a billion or so dim stars.
The same hypothesis might have been applied to the galaxy NGC 4258, but the notion of such a cluster's existing in NGC 4258 was severely undermined when astronomers measured the speed of a ring of dust and gas rotating close to the galaxy's center. From its speed, they calculated that the core's density is more than 40 times the density estimated for any other galaxy. If the center of NGC 4258 were a star cluster, the stars would be so closely spaced that collisions between individual stars would have long ago torn the cluster apart.
The same hypothesis might have been applied to the galaxy NGC 4258, but the notion of such a cluster's existing in NGC 4258 was severely undermined when astronomers measured the speed of a ring of dust and gas rotating close to the galaxy's center. From its speed, they calculated that the core's density is more than 40 times the density estimated for any other galaxy. If the center of NGC 4258 were a star cluster, the stars would be so closely spaced that collisions between individual stars would have long ago torn the cluster apart.
题目：
The passage asserts which of the following about the existence of black holes?
选项:
A、Astronomers first speculated about the existence of black holes when they observed gas whirling around the center of a particular galaxy.
B、Evidence used to argue for the existence of black holes is indirect, coming from their presumed effects on other astronomical bodies.
C、Recent observations of certain astronomical bodies have offered proof.
D、A considerable body of evidence suggests the existence of black holes, even though their behavior is not completely consistent with the laws of physics.
E、Many astronomers are skeptical about certain recent evidence that has been used to argue for the existence of black holes.
答案:
B
0评分
1287浏览
[Undefined]
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.
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？
0评分
3634浏览
[Undefined]
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
0评分
4015浏览
[Undefined]
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
0评分
1336浏览
[Undefined]
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？
0评分
2992浏览
[GWD]
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
0评分
2075浏览
0评分
1332浏览
[Undefined]
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
0评分
1401浏览
[Undefined]
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
0评分
330806浏览
0评分
337932浏览
