GMAT考满分·题库

搜索

收录题目9362道

搜索结果共9178条

来源 题目内容
Magoosh Those who maintain that technology is negatively rewiring our brains have several common targets: GPS devices eroding our ability to conceptualize space, the many hyperlinks of the Internet driving us to distraction, and with our smartphones our working memory is impaired when doing something as fundamental as recalling a string of digits.
Ready4

A bag has 32 yellow, red, blue and green balls. If one ball is drawn from the bag at random, the probability that it will be green is 0.5, and the probability that it will be blue is 0.25. What is the probability that the ball will be either red or yellow?
Ready4

A company will select 1 of 8 eligible employees to work its second shift and 2 of 12 eligible employees to work its third shift. If none of the employees is eligible to work both shifts, how many different sets of 3 employees are there to work these shifts?
190310 A teacher graded 10 students. If the teacher added X points to the score of each student on the basis of the original one, or reduced Y points to that of each student. What was the difference between the average scores in the two cases?
1：X+Y=20
2：X-Y =4
Ready4

     In semi-aquatic ecosystems, bodies of water present peculiar difficulties for the hunting strategies of spiders. Ponds, lakes, and rivers can provide unnavigable escape vectors for prey organisms, making it likely that predators will lose out on valuable nutritional resources. The water spider Dolomedes, in particular, demonstrates adaptations that allow it to take advantage of waterborne food sources.

     The difficulty that members of the species Dolomedes face is best evidenced by the typical hunting strategies of terrestrial spiders. All spiders produce silk and arboreal species generally spin their silk into fine, latticework structures that they suspend in the environment to trap passing arthropods, which entangle themselves due to the exigencies of the forested ecosystem. In environs lacking tree coverage or comparable large structures, however, web-hunting becomes inefficient, and other strategies of predation have to be pursued. That many spider species persist in environments lacking significant tree coverage suggests that certain behavioral adaptations enable them to locate food effectively in a variety of environmental circumstances.

     One such adaptation is the proactive use of water bodies by Dolomedes, who eschew silk in favor of water tension, which they use to monitor the movements of prey animals. Organisms fall into a pond, lake, or river, and send waves vibrating from the point of impact across the surface of the pool. Dolomedes uses these vibrations to locate and capture the fallen organism. For arboreal spiders, who can only monitor the vibrations caused by insects caught in the webs they've spun, this is useless information. Such a hunting strategy does not require that the arboreal spiders pay attention to extraneous prey when other prey is acquired in abundance by other adaptations. In comparison, Dolomedes acquires its prey by yet another aquatic adaptation, using a coat of tiny, hydrophobic hairs that allow the spider to submerge itself in the liquid environment. By causing a pocket of air to gather and surround the surface of the spider's body, these hairs allow Dolomedes to submerge itself in water, thus giving it access to sources of prey closed off to other species.
A key decision required of advertising managers is whether a "hard-sell" or "soft-sell" strategy Line is appropriate for a specific target market. The hard-sell approach involves the use of direct, forceful claims regarding the benefits of the advertised brand over competitors' offerings. In contrast, the soft-sell approach involves the use of advertising claims that imply superiority more subtly.One positive aspect of the hard-sell approach is its use of very simple and straightforward product claims presented claims presented as explicit conclusions, with little room for confusion regarding the advertiser's message. However, some consumers may resent being told what to believe and some may distrust the message. Resentment and distrust often lead to counterargumentation and to boomerang effects where consumers come to believe conclusions diametrically opposed to conclusions endorsed in adverrising claims, By contrast, the risk of boomerang erects is greatly reduced with soft-sell approaches. One way to implement the soft-sell approach is to provide information that implies the main conclusions the advertiser wants the consumer to draw, but leave the conclusions themselves unstated. Because consumers are invited to make up their own minds, implicit conclusions reduce the risk of resentment, distrust, and counter argumentation.Recent [hl:2]research[/hl:2] on consumer memory and judgment suggests another advantage of implicit conclusions. Beliefs or conclusions that are self-generated are more accessible from memory than beliefs from conclusions provided explicitly by other individuals, and thus have a greater impact on judgment and decision making. Moreover, self-generated beliefs are often perceived as more accurate and valid than the beliefs of others, because other individuals may be perceived as less knowledgeable, or may be perceived as manipulative or deliberately misleading.Despite these advantages, implicit conclusions may not always be more effective than explicit Conclusions. One risk is that some consumers may fail to draw their own conclusions and thus miss the point of the message. .Inferential activity is likely only when consumers are motivated and able to engage in effortful cognitive processes. Another risk is that some con-Summers may draw conclusions Other than the one intended ,Even if inferential activity is likely there is no guarantee that consumers will follow the path provided by the advertiser. Finally, a third risk is that consumers may infer the intended conclusion but question the validity of their inference.
Since the 1850s researchers have tried to show that variations in seasonal weather are connected in some ways with sunspots, the outward sign of an increase in the Sun's activity. However, sciences lacked evidence supporting such a link until the mid-1980s,when van Loon and Labitzke compiled statistical evidence suggesting that a link exists and that it involves winds in the upper atmosphere above the equator which reverse their direction，from east to west or west to east, every twelve to fifteen months. This phenomenon is called the quasi-biennial oscillation(QBO), and although meteorologists have known about the QBO since the 1950s,until the 1980s no one recognized a subtle but statistically significant link between the QBO and certain pattern of weather. When the west to east direction of winds in the upper atmosphere coincides with periods of high solar activity that occur approximately every eleven years, winters in the eastern and central United States are very cold.On this basis, some meteorologists predicted that the winter of 1988-1989 in the United States would be severe. However, the winter was a mild one overall, and the meteorologists' attempt to make the connection between the Sun and weather on the Earth appeared unsuccessful, until Barston and Liverzey proposed a hypothesis explaining why the prediction had failed. They argued that the prediction had not taken into account another important element in the climate: the more or less regular pattern of fluctuations in the temperature of the surface waters of the tropical Pacific Ocean.Barston and Livezey noted that when the water temperature is abnormally high-the phenomenon called EL Nino—the chances of cold winter weather over North America increase. The opposite situation, when surface temperatures are well below normal—La Nina—is far less common. In fact, until late 1988 no one had seen the combination of La Nina, westerly winds in the upper atmosphere, and high solar activity. Thus, according to Barston and Livezey, La Nina canceled out the effect of the other two climatic factors and caused the mild winter of 1988-1989. Although this hypothesis is plausible, much research remains to be done before meteorologists can establish and explain the effects of increased solar activity on seasonal weather changes.
Press ReleaseIn a finding that may challenge popular notions of body fat and health, researchers at Beth Israel Deaconess Medical Center (BIDMC) have shown how fat cells can protect the body against diabetes. The results may lead to a new therapuetic strategy for preventing and treating type 2 diabetes and obesity-related metabolic diseases, the author says. In the study, the BIDMC researchers pinpointed the fat gene and its effect in mouse models of human obesity and insulin resistance and reported supporting evidence from fat tissue samples from both lean and obese people. "Two things were surprising -- first, that a lone gene could shift the metabolism of the fat cell so dramatically and then, that turning on this master switch selectively in adipose tissue is beneficial to the whole body," said senior author Barbara Kahn MD, the George R. Minot Professor of Medicine at Harvard Medical School and Vice Chair of the Department of Medicine at BIDMC. Twelve years ago, Kahn first demonstrated that fat cells are a master regulator of healthy levels of glucose and insulin in mice and require sugar to do the job.Type 2 diabetes mellitus is now recognized as a metabolic syndrome and although the treatment paradigm has shifted from one that focuses solely on glycemic control to one addressing global cardiovascular risk factors in a particular individual, glycemic control remains one of the key challenges that the physician faces in his daily practice. The practicing physician must be familiar with the basic pharmacology of the various classes of hypoglycemic drugs to ensure its effective and rational use. This is becoming an increasingly complicated task given the rapid pace of progress in diabetes therapy. There is also a need to appreciate the pathophysiology of type 2 diabetes and the concept of insulin resistance and b-cell dysfunction, and how this may influence the choice of therapeutic agents in any particular patient. JournalType 2 diabetes is still not satisfactorily managed anywhere in the world, thereby accounting for the considerable morbidity and mortality from diabetes-related complications. Epidemiologically, the Asia-Pacific region alone accounts for nearly 50% of the world's diabetic patients, 95% or more being type 2 diabetics. Singapore has one of the highest prevalence of diabetes in the region. The National Health Survey of Singapore in 1998 estimated an overall prevalence of 9.0% among adults 18 to 69 years of age, with rates highest among Indians (15.8%) and Malays (11.3%). Diabetes alone is the sixth commonest cause of death, excluding deaths secondary to cardiovascular and renal complications.MagazineType 2 diabetes is still not satisfactorily managed anywhere in the world, thereby accounting for the considerable morbidity and mortality from diabetes-related complications. Epidemiologically, the Asia-Pacific region alone accounts for nearly 50% of the world's diabetic patients, 95% or more being type 2 diabetics. Singapore has one of the highest prevalence of diabetes in the region. The National Health Survey of Singapore in 1998 estimated an overall prevalence of 9.0% among adults 18 to 69 years of age, with rates highest among Indians (15.8%) and Malays (11.3%). Diabetes alone is the sixth commonest cause of death, excluding deaths secondary to cardiovascular and renal complications.
OG18-数学分册 The sequence $$s_{1}$$, $$s_{2}$$, $$s_{3}$$, ...$$s_{n}$$,... is such that $$s_{n} = \frac{1}{n} - \frac{1}{n +1}$$ for all integers $$n\ge 1$$. If k is a positive integer, is the sum of the first k terms of the sequence greater than $$\frac{9}{10}$$?(1) k > 10(2) k < 19
A can manufacturing company has 5 identical machines, each of which produces cans at the same constant rate. How many cans will all 5 machines produce running simultaneously for z hours?(1)Running simultaneously, 3 of the machines produce 72,000 cans in 2z hours.(2)Running simultaneously, 2 of the machines produce 24,000 cans in z hours.
OG12 OG15 OG16 OG17 GMAT、gmat题库、gmat模考、gmat考满分Each · in the mileage table above represents an entry indicating the distance between a pair of the five cities. If the table were extended to represent the distances between all pairs of 30 cities and each distance were to be represented by only one entry, how many entries would the table then have?
GWD The passage contains information that answers which of the following questions?I. What portion of the research dollar in this country is spent each year by the federal government?II. Under what circumstances is an industrial giant likely to invest heavily in innovation?III. Why might a monopolistic producer want to suppress an innovation?
% of Day 1 shoppers returned to the store on Day 3.Shoppers at Retailer R who purchased substitute items from other manufacturers on Day 1 paid a total amount that was approximately of the total all Day 1 shoppers would have paid had each of them been able to purchase Product X on Day 1.
OG16 OG17 OG18 OG19 OG20 OG2022 GMAT、gmat题库、gmat模考、gmat考满分The smaller rectangle in the figure above represents the original size of a parking lot before its length and width were each extended by w feet to make the larger rectangular lot shown. If the area of the enlarged lot is twice the area of the original lot, what is the value of w?
PREP07 Test 1 Of the 25 cars sold at a certain dealership yesterday, some had automatic transmission and some had antilock brakes. How many of the cars had automatic transmission but not antilock brakes?(1) All of the cars that had antilock brakes also had automatic transmission.(2) 2 of the cars had neither automatic transmission nor antilock brakes.
190113 还原机经选题: 文字题&amp;几何 According to the picture, the bottom radius of the conical funnel is R and the height is 16. A person pours water into this funnel, and the conical bottom radius of water is r. r/R = 3/4. What is the height of the cone formed by water?
Ready4
City City City City City City
City X X X X X
City X   X X X X
City X X X X
City X X X
City X X
City X

Each X in the frequent flyer table above represents an entry indicating the number of frequent flyer miles earned for flying one way between a pair of cities on a particular airline. As part of a promotion, the airline awards an additional 500 frequent flyer miles for all flights originating from City . If the table were extended to represent the frequent flyer miles for flying between all pairs of 20 cities on the airline and each frequent flyer mile award were to be represented by only one entry, how many entries would the table then have?
Ready4 According to television networks, software tracking social media sentiment has proved useful to predict the outcome of political elections.
People associate global warming with temperature, but the phrase is misleading—it fails to mention the relevance of water. Nearly every significant indicator of hydrological activity—rainfall, snowmelt, glacial melt—is changing at an accelerating pace (one can arbitrarily pick any point of the hydrological cycle and notice a disruption). One analysis pegged the increase in precipitation at 2 percent over the century. In water terms this sounds auspicious, promising increased supply, but the changing timing and composition of the precipitation more than neutralizes the advantage. For one thing, it is likely that more of the precipitation will fall in intense episodes, with flooding a reasonable prospect. In addition, while rainfall will increase, snowfall will decrease. Such an outcome means that in watersheds that depend on snowmelt, like the Indus, Ganges, Colorado river basins, less water will be stored as snow, and more of it will flow in the winter, when it plays no agricultural role; conversely, less of it will flow in the summer, when it is most needed. One computer model showed that on the Animas River an increase in temperature of 3.6 degrees Fahrenheit would cause runoff to rise by 85 percent from January to March, but drop by 40 percent from July to September. The rise in temperature increases the probability and intensity of spring floods and threatens dam safety, which is predicated on lower runoff projections. Dams in arid areas also may face increased sedimentation, since a 10 percent annual increase in precipitation can double the volume of sediment washed into rivers. The consequences multiply. Soil moisture will intensify at the highest northern latitudes, where precipitation will grow far more than evaporation and plant transpiration but where agriculture is nonexistent. At the same time, precipitation will drop over northern mid-latitude continents in summer months, when ample soil moisture is an agricultural necessity. Meanwhile the sea level will continue to rise as temperatures warm, accelerating saline contamination of freshwater aquifers and river deltas. The temperature will cause increased evaporation, which in turn will lead to a greater incidence of drought. Perhaps most disturbing of all, the hydrologic cycle is becoming increasingly unpredictable. This means that the last century's hydrological cycle—the set of assumptions about water on which modern irrigation is based—has become unreliable. Build a dam too large, and it may not generate its designed power; build it too small, and it may collapse or flood. Release too little dam runoff in the spring and risk flood, as the snowmelt cascades downstream with unexpected volume; release too much and the water will not be available for farmers when they need it. At a time when water scarcity calls out for intensified planning, planning itself may be stymied.
Magoosh K is a set of integers such thati) if x is in K, then 2x is in Kii) if each of x and y is in K, then x + y is in KIs 15 in K?(1) 1 is in K.(2) 3 is in K.