单选题While agents and editors often______their market and sometimes reject good or even great works, they do prevent a vast quantity of truly______writing from being published.(A) displease… anonymous(B) misunderstand … execrable(C) overestimate … repulsive(D) essay… relevant(E) avoid… clever

单选题The passage suggests which of the following about scientists' conception of the function of the amino acid alanine in the rhizobia's nitrogen fixation process?

单选题According to the author, at present people derive the bulk of their impression of the past from which of the following mediums?

单选题TICKLISH:

单选题The assertion in the third paragraph that quantum mechanics forbids the duplication of unknown quantum bits tends to support the view that(A) the simple classical triplet code used in repetition code would probably fail for quantum error correction(B) the process of copying information in quantum mechanics affects the value of the thing copied(C) computation codes in quantum mechanics tend to be more susceptible to noise than those in classical mechanics(D) quantum mechanics tends to be more limited in its potential applications than classical mechanics(E) quantum mechanics is ill-suited to the problems of error correction

单选题Lifeexpectancyamongadults45and65yearsofagebyfamilyincome,sex,andrace:UnitedStates,averageannual1979-89

单选题IfABCDEisaregularpentagon,whatisthemeasureof∠EBD?

单选题WILY : SLY ::

单选题PROTRUSION:(A) deep recess(B) strong dislike(C) growing scarcity(D) illusion(E) chaos

问答题如果作者能提供新证据并明确表明当地居民对于水上娱乐设施有很大需求，他的建议必定会更加获得青睐。

问答题Task2: Argument Analysis Directions: In 30 minutes, prepare a critical analysis of an argument expressed in a short paragraph. You may not offer an analysis of any other argument. Write your essay on the lined page that follows. As you critique the argument, think about the author's underlying assumptions. Ask yourself whether any of them are questionable. Also evaluate any evidence the author brings up. Ask yourself whether it actually supports the author's conclusion. In your analysis, you may suggest additional kinds of evidence to reinforce the author's argument. You may also suggest methods to refute the argument, or additional data that might be useful to you as you assess the soundness of the argument. You may not, however, present your personal views on the topic. Your job is to analyze the elements of an argument, not to support or contradict that argument. Faculty members from various institutions will judge your essay, assessing it on the basis of your skill in the following areas: · Identification and assessment of the argument's main elements · Organization and articulation of your thoughts · Use of relevant examples and arguments to support your case · Handling of the mechanics of standard written English Topic The following appeared in a letter to the editor in the journal Health Matters. Statistics gathered over the past three decades show that the death rate is higher among those who do not have jobs than among those with regular employment. Unemployment, just like heart disease and cancer, is a significant health issue. While many health care advocates promote increased government funding for medical research and public health care, it would be folly to increase government spending if doing so were to affect the nation's economy adversely and ultimately cause a rise in unemployment. A healthy economy means healthy citizens.

问答题 Simple Probability and Outcomes These questions will test your knowledge of operations involving simple probability and outcomes. Answer the following questions.

问答题作者希望通过引用一项调查来巩固他的观点，但是这项调查结果本身可以有不同的、甚至是互相抵触的解读方式。 *提示：使用subject to。

问答题 Perimeter, Area, and Volume These questions will test your knowledge of operations involving perimeter, area, and volume. Answer the following questions.

问答题{{U}}Traditionally, pollination by wind has been viewed as a reproductive process marked by random events in which the vagaries of the wind are compensated for by the generation of vast quantities of pollen, so that the ultimate production of new seeds is assured at the expense of producing much more pollen than is actually used.{{/U}} Because the potential hazards pollen grains are subject to as they are transported over long distances are enormous, wind-pollinated plants have, in the view above, compensated for the ensuing loss of pollen through happenstance by virtue of producing an amount of pollen that is one to three orders of magnitude greater than the amount produced by species pollinated by insects. {{U}}However, a number of features that are characteristic of wind-pollinated plants reduce pollen waste.{{/U}} For example, many wind-pollinated species fail to release pollen when wind speeds are low or when humid conditions prevail. Recent studies suggest another way in which species compensate for the inefficiency of wind pollination. These studies suggest that species frequently take advantage of the physics of pollen motion by generating specific aerodynamic environments within the immediate vicinity of their female reproductive organs. {{U}}It is the morphology of these organs that dictates the pattern of airflow disturbances through which pollen must travel.{{/U}} The speed and direction of the airflow disturbances can combine with the physical properties of a species' pollen to produce a species-specific pattern of pollen collision on the surfaces of female reproductive organs. Provided that these surfaces are strategically located, the consequences of this combination can significantly increase the pollen-capture efficiency of a female reproductive organ. {{U}}A critical question that remains to be answered is whether the morphological attributes of the female reproductive organs of wind-pollinated species are evolutionary adaptations to wind pollination{{/U}} or are merely fortuitous. A complete resolution of the question is as yet impossible since adaptation must be evaluated for each species within its own unique functional context. {{U}}However, it must be said that, while evidence of such evolutionary adaptations does exist in some species, one must be careful about attributing morphology to adaptation.{{/U}} For example, the spiral arrangement of scale-bract complexes on ovule-bearing pine cones, where the female reproductive organs of conifers are located, is important to the production of airflow patterns that spiral over the cone's surfaces, thereby passing airborne pollen from one scale to the next. However, these patterns cannot be viewed as an adaptation to wind pollination because the spiral arrangement occurs in a number of non-wind-pollinated plant lineages and is regarded as a characteristic of vascular plants, of which conifers are only one kind, as a whole. Therefore, the spiral arrangement is not likely to be the result of a direct adaptation to wind pollination.

问答题关于利润降低问题的分析完全没有完结，我们还需要思考有没有其他能导致利润降低的因素，例如上升的运营成本。

问答题(1) When a molten metal or metallic alloy is cooled to a solid, a crystalline structure is formed that depends on the particular alloy composition. (2) In contrast, molten nonmetallic glass-forming materials, when cooled, do not assume a crystalline structure, but instead retain a structure somewhat like that of the liquid—an amorphous structure. (3) At room temperature, the natural long-term tendency for both types of materials is to assume the crystalline structure. (4) {{U}}The difference between the two is in the kinetics or rate of formation of the crystalline structure, which is controlled by factors such as the nature of the chemical bonding and the ease with which atoms move relative to each other.{{/U}} (5) Thus, in metals, the kinetics favors rapid formation of a crystalline structure, whereas in nonmetallic glasses the rate of formation is so slow that almost any cooling rate is sufficient to result in an amorphous structure. Select the sentence in which the author illustrates the causes of the rate of formation of the crystalline structure.

问答题It is well known that biological changes at the molecular level have morphogenetic consequences, consequences affecting the formation and differentiation of tissues and organs. It is superfluous to point out that gene mutations and disturbances of the biosynthetic processes in the embryo may result in abnormalities in the morphology (structure) of an organism. However, whereas much is known about causes and consequences at the molecular level, and in spite of an enormous accumulation of chemical and morphological data on embryos of various kinds, {{U}}our understanding of how genes control morphogenesis is still far from complete. Perhaps one reason for this is that molecular biologists and morphologists speak different languages.{{/U}} Whereas the former speak about messenger-RNA and conformational changes of protein molecules, the latter speak of ectoderms, hypoblasts, and neural crests. {{U}}One solution to this predicament is to try to find some phenomena relevant to morphogenesis which both the molecular biologist and the morphologist can understand and discuss.{{/U}} As morphogenesis must be basically the result of changes in behavior of the individual cells, it seems logical to ask morphologists to describe the morphogenetic events observed in terms of changes in cellular contact, changes in the rate of proliferation of cells, or similar phenomena. Once this is done, it may be appropriate to ask questions about the molecular background for these changes. One may, for instance, ask whether variations in cell contact reflect alterations in the populations of molecules at the cell surface, or one may inquire about the molecular basis for the increased cell mobility involved in cell dispersion. Studies of this kind have been carried out with cells released from tissues in various ways and then allowed to reveal their behavior after being spread out into a thin layer. In many cases, such cells show the ability to reaggregate, after which different cell types may sort themselves out into different layers and even take part in still more intricate morphogenetic events. But in most cases, the behavior of cells in the intact embryo is difficult to study because of the thickness and opacity of the cell masses. The sea urchin embryo, however, has the advantage that it is so transparent that each cell can be easily observed throughout development. Thus, {{U}}by recording the development of a sea urchin embryo with time-lapse photography, the research scientist might discover previously unknown features of cellular behavior. Perhaps the study of the sea urchin in this manner can provide a medium by which the molecular biologist and the morphologist can begin communicating with each other more effectively about the way in which genes control morphogenesis.{{/U}}

问答题{{U}}Bracken fern has been spreading from its woodland strongholds for centuries,{{/U}} but the rate of encroachment into open countryside has lately increased alarmingly throughout northern and western Britain. A tough competitor, bracken {{U}}reduces the value of grazing land{{/U}} by crowding out other vegetation. The fern is itself poisonous to livestock, and also encourages proliferation of sheep ticks, which {{U}}not only attack sheep but also transmit diseases{{/U}}. No less important to some people are bracken's effects on threatened habitats and on the use of uplands for recreational purposes, even though many appreciate its beauty. {{U}}Biological controls may be the only economic solution.{{/U}} One potentially cheap and self-sustaining method of halting the spread of bracken is to introduce natural enemies of the plant. Initially unrestrained by predators of their own, foreign predators are likely to be able to multiply rapidly and overwhelm intended targets. Because bracken occurs throughout the world, there is plenty of scope for this approach. Two candidates, both moths from the Southern Hemisphere, are now being studied. {{U}}Of course, biological control agents can safely be released only if it can be verified that they feed solely on the target weed. The screening tests have so far been fraught with difficulties.{{/U}} The first large shipment of moths succumbed to a disease. Growing enough bracken indoors is difficult, and the moths do not readily exploit cut stems. These are common problems with rearing insects for biological control. {{U}}Other problems can be foreseen. Policymakers need to consider many factors and opinions such as the cost of control compared to existing methods, and the impact of the clearance of bracken on the landscape, wildlife, and vegetation.{{/U}} In fact, scientists already have much of the information needed to assess the impact of biological control of bracken, but it is spread among many individuals, organizations, and government bodies. The potential gains for the environment are likely to outweigh the losses because few plants, insects, mammals, and birds live associated only with bracken, and many would benefit from a return of other vegetation or from a more diverse mosaic of habitats. But legal consequences of attempts at biological control present a potential minefield. For example, many rural tenants still have the right of "estoyers", the right to cut bracken as bedding for livestock and uses. What would happen if they were deprived of these rights? Once a biological control agent is released, it is difficult to control its speed. What consideration is due landowners who do not want to control bracken? According to law, the release of the biological control agents must be authorized by the secretary of state for the environment. But Britain lacks the legal and administrative machinery to assemble evidence for and against release.

问答题{{U}}A mysterious phenomenon is the ability of over-water migrants to travel on course.{{/U}} Birds, bees, and other species can keep track of time without any sensory cues from the outside world, and such "biological clocks" clearly contribute to their "{{U}}compass sense{{/U}}". For example, they can use the position of the Sun or stars, along with the time of day, to find north. But compass sense alone cannot explain how birds navigate the ocean: after a flock traveling east is blown far south by a storm, it will assume the proper northeasterly course to compensate. Perhaps, some scientists thought, migrants determine their geographic position on Earth by celestial navigation, almost as human navigators use stars and planets, but this would demand of the animals a fantastic map sense. Researchers now know that some species have a magnetic sense, which might allow migrants to determine their geographic location by detecting variations in the strength of the Earth's magnetic field.