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Industrialists from the country Distopia were accused of promoting the Distopian intervention in the Arcadian civil war merely to insure that the industrialists' facilities in Arcadia made substantial profits during the war. Yet this cannot be the motive since, as the Distopians foresaw, Distopia's federal expenses for the intervention were eight billion dollars, whereas, during the war, profits from the Distopian industrialists' facilities in Arcadia totaled only four billion dollars.Which of the following, if true, exposes a serious flaw in the argument made in the second sentence above?
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Last year the county park system failed to generate enough revenue to cover its costs. Any business should be closed if it is unprofitable, but county parks are not businesses. Therefore, the fact that county parks are unprofitable does not by itself justify closing them.The pattern of reasoning in the argument above is most closely paralleled in which one of the following?
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Rumored declines in automobile-industry revenues are exaggerated. It is true that automobile manufactures' share of the industry's revenues fell from 65 percent two years ago to 50 percent today, but over the same period suppliers of automobile parts had their share increase from 15 percent to 20 percent and service companies (for example, distributors, dealers, and repairers) had their share increase from 20 percent to 30 percent.Which one of the following best indicates why the statistics given above provide by themselves no evidence for the conclusion they are intended to support?
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In 1963, Congress approved the Community Mental Health Centers Act, which outlined plans to release the mentally ill from institutions, incorporate these individuals into their communities, and provide outpatient treatment. Leading associations of mental health professionals overwhelmingly applauded these goals and approved of these plans because, the experts said, the treatment rather than the institutional environment was the crucial element for the welfare of these patients. Within twenty years, state authorities succeeded in discharging 95% of these patients from institutional care. In 1983, however, executives from these same professional associations said that the plight of the mentally ill was worse than ever. Which if the following, if true, best resolves the paradox in the above passage?
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A program instituted in a particular state allows parents to prepay their children's future college tuition at current rates. The program then pays the tuition annually for the child at any of the state s public colleges in which the child enrolls. Parents should participate in the program as a means of decreasing the cost for their children's college education.Which of the following, if true, is the most appropriate reason for parents not to participate in the program?
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Which if the following is a possible value of y- 4 if $$({3}{y}-{8})^{2}={2},{500}$$?
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A think-tank in Michigan has announced a controversial new finding. It concludes that efforts to combat high emissions from cars by taxing gasoline and SUVs are misplaced; rather, governments should be providing consumers with tax incentives to purchase large cars and carpooling with their neighbors to work. They estimate that such a plan would reduce national gas emissions by 23% over the next decade.Which of the following, if true, casts the greatest doubt on the likely effectiveness of this recommendation?
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PREP07 Test 1
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The Cost of a square slab is proportional to its thickness and also proportional to the square of its length. What is the cost of a square slab that is 3 meters long and 0.1 meter thick?(1) The cost of a square slab that is 2 meters long and 0.2 meter thick is $160 more than the cost of a square slab that is 2 meters long and 0.1 meter thick.(2) The cost of a square slab that is 3 meters long and 0.1 meter thick is $200 more than the cost of a square slab that is 2 meters long and 0.1 meter thick.
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The function of capital markets is to facilitate an exchange of funds among all participants, and yet in practice we find that certain participants are not on a par with others. Members of society have varying degrees of market strength in terms of information they bring to a transaction, as well as of purchasing power and creditworthiness, as defined by lenders.For example, within minority communities, capital markets do not properly fulfill their functions; they do not provide access to the aggregate flow of funds in the United States. The financial system does not generate the credit or investment vehicles needed for underwriting economic development in minority areas. The problem underlying this dysfunction is found in a rationing mechanism affecting both the available alternatives for investment and the amount of financial resources. This creates a distributive mechanism penalizing members of minority groups because of their socioeconomic differences from others. The existing system expresses definite socially based investment preferences that result from the previous allocation of income and that influence the allocation of resources for the present and future. The system tends to increase the inequality of income distribution. And, in the United States economy, a greater inequality of income distribution leads to a greater concentration of capital in certain types of investments.Most traditional financial-market analysis studies ignore financial markets' deficiencies in allocation because of analysts' inherent preferences for the simple model of perfect competition. Conventional financial analysis pays limited attention to issues of market structure and dynamics, relative costs of information, and problems of income distribution. Market participants are viewed as acting as entirely independent and homogeneous individuals with perfect foresight about capital-market behavior. Also, it is assumed that each individual in the community at large has the same access to the market and the same opportunity to transact and to express the preference appropriate to his or her individual interest. [hl:4]Moreover, it is assumed that transaction costs for various types of financial instruments (stocks, bonds, etc.) are equally known and equally divided among all community members.[/hl:4]
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The new school of political history that emerged in the 1960's and 1970's sought to go beyond the traditional focus of political historians on leaders and government institutions by examining directly the political practices of ordinary citizens. Like the old approach, however, this new approach excluded women. The very techniques these historians used to uncover mass political behavior in the nineteenth century United States - quantitative analyses of election returns, for example--were useless in analyzing the political activities of women, who were denied the vote until 1920.By redefining "political activity", historian Paula Baker has developed a political history that includes women. She concludes that among ordinary citizens, political activism by women in the nineteenth century prefigured trends in twentieth century politics. Defining "politics" as "any action taken to affect the course of behavior of government or of the community", Baker concludes that, while voting and holding office were restricted to men, women in the nineteenth century organized themselves into societies committed to social issues such as temperance and poverty. In other words, Baker contends, women activists were early practitioners of nonpartisan, issue oriented politics and thus were more interested in enlisting lawmakers, regardless of their party affiliation, on behalf of certain issues than in ensuring that one party another won an election. In the twentieth century, more men drew closer to women's ideas about politics and took up modes of issue oriented politics that Baker sees women as having pioneered.
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Two recent publications offer different assessments of the career of the famous British nurse Florence Nightingale. A book by Anne Summers seeks to debunk the idealizations and present a reality at odds with Nightingale's heroic reputation. According to Summers, Nightingale's importance during the Crimean War has been exaggerated：not until near the war's end did she become supervisor of the female nurses. Additionally, Summers writes that the contribution of the nurses to the relief of the wounded was at best marginal. The prevailing problems of military medicine were caused by army organizational practices, and the addition of a few nurses to the medical staff could be no more than symbolic. Nightingale's place in the national pantheon, Summers asserts, is largely due t0 the propagandistic efforts of contemporary newspaper reporters.By contrast, the editors of a new volume of Nightingale's letters view Nightingale as a person who significantly influenced not only her own age but also subsequent generations. They highlight her ongoing efforts to reform sanitary conditions after the war. For example, when she learned that peacetime living conditions in British barracks were so horrible that the death rate of enlisted men far exceeded that of neighboring civilian populations, she succeeded in persuading the government to establish a Royal Commission on the Health of the Army. She used sums raised through public contributions to found a nurses' training hospital in London. Even in administrative matters, the editors assert, her practical intelligence was formidable：as recently as 1947 the British Army's medical services were still using the cost-accounting system she had devised in the 1860's.I believe that the evidence of her letters supports continued respect for Nightingale's brilliance and creativity. When counseling a village schoolmaster to encourage children to use their faculties of observation, she sounds like a modern educator. Her insistence on classifying the problems of the needy in order to devise appropriate treatments is similar to the approach of modern social workers. In sum, although Nightingale may not have achieved all of her goals during the Crimean War, her breadth of vision and ability to realize ambitious projects have earned her an eminent place among the ranks of social pioneers.
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Neotropical coastal mangrove forests are usually"zonal,"with certain mangrove species found predominantly in the seaward portion of the habitat and other mangrove species on the more landward portions of the coast. The earliest research on mangrove forests produced descriptions of species distribution from shore to land, without exploring the causes of the distributions.The idea that zonation is ca used by plant succession. was first expressed by J. H. Davis in a study of Florida mangrove forests. According to Davis' scheme, the shoreline is being extended in a seaward direction because of the"land-building"role of mangroves t which l by trapping sediments over time, extend the shore. As a habitat gradually becomes more in land as the shore extends, the"land-building"species are replaced. This continuous process of accretion and succession would be interrupted only by hurricanes or storm flushings.Recently the universal application of Davis' succession paradigm has been challenged. It appears that in areas where weak currents and weak tidal energies allow the accumulation of sediments, mangroves will follow land formation and accelerate the rate of soil accretion；succession will proceed according to Davis' scheme. But on stable coastlines, the distribution of mangrove species results in other patterns of zonation；"land building"does not occur.To find a principle that explains the various distribution patterns, several researchers have looked to salinity and its effects on mangroves. While mangroves can develop in fresh water,they can also thrive in salinities as high as 2. 5 times that of seawater. However, those mangrove species found in freshwater habitats do well only in the absence of competition, thus suggesting that salinity tolerance is a critical factor in competitive success among mangrove species. Research suggests that mangroves will normally dominate highly saline regions, although not because they require salt. Rather, they are metabolically efficient(and hence grow well)in portions of an environment whose high salinity excludes plants adapted to lower salinities. Tides create different degrees of salinity along a coastline. The characteristic mangrove species of each zone should exhibit a higher metabolic efficiency at that salinity than will any potential invader, including other species of mangrove.
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Prior to 1965 geologists assumed that the two giant rock plates meeting at the San Andreas Fault generate heat through friction as they grind past eachother, but in 1965 Henyey found that temperatures in drill holes near the fault were not as elevated as had been expected. Some geologists wondered whether the absence of friction-generated heat could be explained by the kinds of rock composing the fault. Geologists' pre-1965 assumptions concerning heat generated in the fault were based on calculations about common varieties of rocks, such as limestone and granite; but "weaker" materials, such as clays, had already been identified in samples retrieved from the fault zone. Under normal conditions, rocks composed of clay produce far less friction than do other rock types.In 1992 Byerlee tested whether these materials would produce friction 10 to 15 kilometers below the Earth's surface. Byerlee found that when clay samples were subjected to the thousands of atmospheres of pressure they would encounter deep inside the Earth, they produced as much friction as was produced by other rock types. The harder rocks push against each other, the hotter they become; in other words, pressure itself, not only the rocks' properties, affects frictional heating. Geologists therefore wondered whether the friction between the plates was being reduced by pockets of pressurized water within the fault that push the plates away from each other.
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One [hl:2]proposal[/hl:2] for preserving rain forests is to promote the adoption of new agricultural technologies, such as improved plant varieties and use of chemical herbicides, which would increase productivity and slow deforestation by reducing demand for new cropland. Studies have shown that farmers in developing countries who have achieved certain levels of education, wealth, and security of land tenure are more likely to adopt such technologies. But these studies have focused on villages with limited land that are tied to a market economy rather than on the relatively isolated, self-sufficient communities with ample land characteristic of rain-forest regions. A recent [hl:4][hl:3]study[/hl:3][/hl:4] of the Tawahka people of the Honduran rain forest found that farmers with some formal education were more likely to adopt improved plant varieties but less likely to use chemical herbicides and that those who spoke Spanish (the language of the market economy) were more likely to adopt both technologies. Nonland wealth was also associated with more adoption of both technologies, but availability of uncultivated land reduced the incentive to employ the productivity-enhancing tech nologies. Researchers also measured land-tenure security: in Tawahka society, kinship ties are a more important indicator of this than are legal property rights, so researchers measured it by a household's duration of residence in its village. They found that longer residence correlated with more adoption of improved plant varieties but less adoption of chemical herbicides.
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Scientists generally credit violent collisions between tectonic plates, the mobilefragments of Earth's rocky outer shell, with sculpting the planet's surface, as, for example, when what is now the Indian subcontinent collided with Asia, producing the [hl:3]Himalayan Mountains[/hl:3]. However, plate tectonics cannot fully explain certain massive surface features, such as the "superswell" of southern Africa, a vast plateau over 1,000 miles across and nearly a mile high. Geologic evidence shows that southern African has been slowly rising for the past 100 million years, yet it has not experienced a tectonic collision for nearly 400 million years. The explanation may be in Earth's mantle, the layer of rock underlying the tectonic plates and extending down over 1,800 miles to the outer edge of Earth's iron core.Since the early twentieth century, geophysicists have understood that the mantle churns and roils like a thick soup. The relative low density of the hottest rock makes that material buoyant, so it slowly ascends, while cooler, denser rock sinks until heat escaping the molten core warms it enough to make it rise again. While this process of convection was known to enable the horizontal movement of tectonic plates, until recently geophysicists were skeptical of its ability to lift or lower the planet's surface vertically. However, recent technological advances have allowed geophysicists to make three-dimensional "snapshots" of the mantle by measuring vibrations, or seismic waves, set in motion by earthquakes originating in the planet's outer shell and recording the time it takes for them to travel from an earthquake's epicenter to a particular recording station at the surface. Because geophysicists know that seismic waves become sluggish in hot, low-density rock, and speed up in colder, denser regions, they can now infer the temperatures and den- sities in a given segment of the interior. By compiling a map of seismic velocities from thousands of earthquakes across the globe, they can also begin to map temperatures and densities throughout the mantle. These methods have revealed some unexpectedly immense for- mations in the deepest parts of the mantle; the largest of these is a buoyant mass of hot rock directly below Africa's southern tip. Dispelling researchers' initial doubts, [hl:4]computer models[/hl:4] have confirmed that this formation is buoyant enough to rise slowly within the mantle and strong enough to push Africa upward as it rises.
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According to a theory advanced by researcher Paul Martin, the wave of species extinctions that occurred in North America about 11,000 years ago, at the end of the Pleistocene era, can be directly attributed to the arrival of humans, i.e., the Paleoindians, who were ancestors of modern Native Americans. However, anthropologist Shepard Krech points out that large animal species vanished even in areas where there is no evidence to demonstrate that Paleoindians hunted them. [hl:5]Nor were extinctions confined to large animals: small animals, plants, and insects disappeared[/hl:5], presumably not all through human consumption. Krech also contradicts Martin's exclusion of climatic change as an explanation by asserting that widespread climatic change did indeed occur at the end of the Pleistocene. Still, Krech attributes secondary if not primary responsibility for the extinctions to the Paleoindians, arguing that humans have produced local extinctions elsewhere. But, according to historian Richard White, even the attribution of secondary responsibility may not be supported by the evidence. White observes that Martin's thesis depends on coinciding dates for the arrival of humans and the decline of large animal species, and Krech, though aware that the dates are controversial, does not challenge them; yet [hl:3]recent archaeological discoveries[/hl:3] are providing evidence that the date of human arrival was much earlier than 11,000 years ago.
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Behavior science courses should be gaining prominence in business school curricula. Recent theoretical work convincingly shows why behavioral factors such as organizational culture and employee relations are among the few remaining sources of sustainable competitive advantage in modern organizations. Furthermore, [hl:2]empirical evidence[/hl:2] demonstrates clear linkages between human resource (HR) practices based in the behavioral sciences and various aspects of a firm's financial success. Additionally, some of the world's most successful organizations have made unique HR practices a core element of their overall business strategies.Yet the behavior sciences are struggling for credibility in many business schools. Surveys show that business students often regard behavioral studies as peripheral to the mainstream business curriculum. This perception can be explained by the fact that business students, hoping to increase their attractiveness to prospective employers, are highly sensitive to business norms and practices, and current business practices have generally been moving away from an emphasis on understanding human behavior and toward more mechanistic organizational models. Furthermore, the status of HR professionals within organizations tends to be lower than that of other executives.Students' perceptions would matter less if business schools were not increasingly dependent on external funding——form legislatures, businesses, and private foundations——for survival. Concerned with their institutions' ability to attract funding, administrators are increasingly targeting low-enrollment courses and degree programs for elimination.
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Many managers are influenced by dangerous myths about pay that lead to counterproductive decisions about how their companies compensate employees. One such myth is that labor rates, the rate per hour paid to workers, are identical with labor costs, the money spent on labor in relation to the productivity of the labor force. This [hl:5]myth[/hl:5] leads to the assumption that a company can simply lower its labor costs by cutting wages. But labor costs and labor rates are not in fact the same: one company could pay its workers considerably more than another and yet have lower labor costs if that company's productivity were higher due to the talent of its workforce, the efficiency of its work processes, or other factors. The confusion of costs with rates persists partly because labor rates are a convenient target for managers who want to make an impact on their com- pany's budgets. Because labor rates are highly visible, managers can easily compare their company's rates with those of competitors. Furthermore, labor rates often appear to be a company's most malleable financial variable: cutting wages appears an easier way to control costs than such options as reconfiguring work processes or altering product design.The myth that labor rates and labor costs are equivalent is supported by business journalists, who frequently confound the two. For example, prominent business journals often remark on the "high" cost of German labor, citing as evidence the average amount paid to German workers. The myth is also perpetuated by the compensation-consulting industry, which has its own incentives to keep such myths alive. First, although some of these consulting firms have recently broadened their practices beyond the area of compensation, their mainstay continues to be advising companies on changing their compensation practices. Suggesting that a company's performance can be improved in some other way than by altering its pay system may be empirically correct but contrary to the consultants' interests. Furthermore, changes to the compensation system may appear to be simpler to implement than changes to other aspects of an organization, so managers are more likely to find such advice from consultants palatable. Finally, to the extant that changes in compensation create new problems, the consultants will continue to have work solving the problems that result from their advice.
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In 1994, a team of scientists led by David Mckay began studying the meteorite ALH84001, which had been discovered in Antarctica in 1984. Two years later, the McKay team announced that ALH84001, which scientists generally agree originated on Mars, contained compelling evidence that life once existed on Mars. This evidence includes the discovery of organic molecules in ALH84001, the first ever found in Martian rock. Organic molecules-complex, carbon-based compounds-form the basis for terrestrial life. The organic molecules found in ALH84001 are polycyclic aromatic hydrocarbons, or PAH's. When microbes die, their organic material often decays into PAH's.Skepticism about the McKay team's claim remains, however. For example, ALH84001 has been on earth for 13,000 years, suggesting to some scientists that its PAH's might have resulted from terrestrial contamination. However, McKay's team has demonstrated that the concentration of PAH's increases as one looks deeper into ALH84001, contrary to what one would expect from terrestrial contamination. The skeptic's strongest argument, however, is that processes unrelated to organic life can easily produce all the evidence found by McKay' steam, including PAH's. For example, star formation produces PAH's. Moreover, PAH's frequently appear in other meteorites, and no one attributes their presence to life processes. Yet McKay's team notes that the particular combination of PAH's in ALH84001 is more similar to the combinations produced by decaying organisms than to those originating form nonbiological processes.
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Over the last 150 years, large stretches of salmon habitat have been eliminated by human activity:mining, livestock grazing, timber harvesting, and agriculture as well as recreational and urban development. The numerical effect is obvious: there are fewer salmon in degraded regions than in pristine ones; however, habitat loss also has the potential to reduce genetic diversity. This is most evident in cases where it results in the extinction of entire salmon populations. Indeed, most analysts believe that some kind of environmental degradation underlies the demise of many extinct salmon populations. Although some rivers have been recolonized, the unique genes of the original populations have been lost.Large-scale disturbances in one locale also have the potential to alter the genetic structure of populations in neighboring areas, even if those areas have pristine habitats. Why? Although the homing instinct of salmon to their natal stream is strong, a fraction of the fish returning from the sea (rarely more than 15 percent) stray and spawn in nearby streams. Low levels of straying are crucial, since the process provides a source of novel genes and a mechanism by which a location can be repopulated should the fish there disappear. Yet high rates of straying can be problematic because misdirected fish may interbreed with the existing stock to such a degree that any local adaptations that are present become diluted. Straying rates remain relatively low when environmental conditions are stable, but can increase dramatically when streams suffer severe disturbance. The 1980 volcanic eruption of Mount Saint Helens, for example, sent mud and debris into several tributaries of the Columbia River. For the next couple of years, steelhead trout(a species included among the salmonids) returning from the sea to spawn were forced to find alternative streams. As a consequence, their rates of straying, initially 16 percent, rose to more than 40 percent overall.Although no one has quantified changes in the rate of straying as a result of the disturbances caused by humans, there is no reason to suspect that the effect would be qualitatively different than what was seen in the [hl:4]aftermath of the Mount Saint Helens eruption[/hl:4]. Such a dra- matic increase in straying from damaged areas to more pristine streams results in substantial gene flow, which can in turn [hl:5]lower the overall fitness of subsequent generations[/hl:5].
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