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In the coordinate system above, which of the following is the equation of line L?
In an effort to explain why business acquisitions often fail, scholars have begun to focus on the role of top executives of acquired companies. Acquired companies that retain their top executives tend to have more successful outcomes than those that do not. Furthermore, [line:6][hl:1]existing research[/hl:1][/line:6] suggests that retaining the highest-level top executives, such as the CEO(chief executive officer) and COO (chief operating officer), is related more positively to postacquisition success than retaining lower-ranked top executives. However, this explanation, while insightful, suffers from two limitations. First, the focus on positional rank does not recognize the variation in length of service that may exist in top executive posts across companies, nor does it address which particular top executives (with respect to length of service)should be retained to achieve a successful acquisition outcome. Second, the relationship between retained top executives and acquisition outcomes offered by existing research is subject to opposing theoretical explanations related to length of service. The resource-based view (RBV) suggests that keeping acquired company top executives with longer organizational tenure would lead to more successful outcomes, as those executives have idiosyncratic and nontransferable knowledge of the acquired company that would be valuable for the effective implementation of the acquisition. The opposing position, offered by the upper echelons perspective (UEP), suggests that retaining top executives having short organizational tenure would lead to more successful outcomes, as they would have the adaptability to manage most effectively during the uncertainty of the acquisition process.Responding to these limitations, Bergh conducted a study of executive retention and acquisition outcome that focused on the organizational tenure of retained company top executives in 104 acquisitions, followed over 5 years. Bergh considered the acquisition successful if the acquired company was retained and unsuccessful if it was divested. Bergh's findings support the RBV position. Apparently, the benefits of long organizational tenure lead to more successful outcomes than the benefits of short organizational tenure. While longer tenured top executives may have trouble adapting to change, it appears that their perspectives and knowledge bases offer unique value after the acquisition. Although from the UEP position it seems sensible to retain less tenured executives and allow more tenured ones to leave, such a strategy appears to lower the probability of acquisition success.
Scientists studying the physiology of dinosaurs have long debated whether dinosaurs were warm- or cold-blooded. Those who suspect they were warm-blooded point out that dinosaur bone is generally fibro-lamellar in nature; because fibro-lamellar bone is formed quickly, the bone fibrils, or filaments, are laid down haphazardly. Consistent with their rapid growth rate, warm-blooded animals, such as birds and mammals, tend to produce fibro-lamellar bone, whereas reptiles, which are slow-growing and cold-blooded, generally produce bone in which fibrils are laid down parallel to each other. Moreover, like the bone of birds and mammals, dinosaur bone tends to be highly vascularized, or filled with blood vessels. These characteristics, first recognized in the 1930's, were documented in the 1960's by de Ricqlès, who found highly vascularized, fibro-lamellar bone in several groups of dinosaurs. In the 1970's, Bakker cited these characteristics as evidence for the warm-bloodedness of dinosaurs. Although de Ricqlès urged [hl:1]caution[/hl:1], arguing for an intermediate type of dinosaur physiology, a generation of paleontologists has come to believe that dinosaur bone is mammalianlike. In the 1980's, however, Bakker's contention began to be questioned, as a number of scientists found growth rings in the bones of various dinosaurs that are much like those in modern reptiles. Bone growth in reptiles is periodic in nature, producing a series of concentric rings in the bone, not unlike the growth rings of a tree. Recently, Chinsamy investigated the bones of two dinosaurs from the early Jurassic period (208-187 million years ago), and found that these bones also had growth rings; however, they were also partially fibro-lamellar in nature. Chinsamy's work raises a question central to the debate over dinosaur physiology: did dinosaurs form fibro-lamellar bone because of an innately high metabolic rate associated with warm-bloodedness or because of periods of unusually fast growth that occurred under favorable environmental conditions? (Although modern reptiles generally do not form fibro-lamellar bone, [hl:4]juvenile crocodiles[/hl:4] raised under optimal environmental conditions do.) This question remains unanswered; indeed, taking all the evidence into account, one cannot make a definitive statement about dinosaur physiology on the basis of dinosaur bone. It may be that dinosaurs had an intermediate pattern of bone structure because their physiology was neither typically reptilian, mammalian, nor avian.
Until recently, zoologists believed that all species of phocids (true seals), a pinniped family, use a different maternalstrategy than do otariids (fur seals and sea lions), another pinniped family. Mother otariids use a foraging strategy. They acquire moderate energy stores in the form of blubber before arriving at breeding sites and then fast for 5 to 11 days after birth. Throughout the rest of the lactation (milk production) period, which lasts from 4 months to 3 years depending on the species, mother otariids alternately forage at sea, where they replenish their fat stores, and nurse their young at breeding sites. Zoologists had assumed that females of all phocid species, by contrast, use a fasting strategy in which mother phocids, having accumulated large energy stores before they arrive at breeding sites, fast throughout the entire lactation period, which lasts from 4 to 50 days depending on the species. However, recent studies on harbor seals, a phocid species, found that lactating females commenced foraging approximately 6 days after giving birth and on average made 7 foraging trips during the remainder of their 24-day lactation period.The maternal strategy evolved by harbor seals may have to do with their small size and the large proportion of their fat stores depleted in lactation. Harbor seals are small compared with other phocid species such as grey seals, northern elephant seals, and hooded seals, all of which are known to fast for the entire lactation period. Studies show that mother seals of these species use respectively 84 percent, 58 percent, and 33 percent of their fat stores during lactation. By comparison, harbor seals use 80 percent of their fat stores in just the first 19 days of lactation, even though they occasionally feed during this period. Since such a large proportion of their fat stores is exhausted despite feeding, mother harbor seals clearly cannot support all of lactation using only energy stored before giving birth. Though smaller than many other phocids, harbor seals are similar in size to most otariids. In addition, there is already some evidence suggesting that the [hl:4][hl:3][hl:2][hl:1]ringed seal[/hl:1][/hl:2][/hl:3][/hl:4] , a phocid species that is similar in size to the harbor seal, may also use a maternal foraging strategy.
Anole lizard species that occur together (sympatrically) on certain Caribbean islandsoccupy different habitats: some live only in the grass, some only on tree trunks, and some only on twigs. These species also differ morpho-logically: grass dwellers are slender with long tails, tree dwellers are stocky with long legs, twig dwellers are slender but stubby-legged. [hl:1]What is striking about these lizards is not that coexisting species differ in morphology and habitat use (such differences are common among closely related sympatric species), but that the same three types of habitat specialists occur on each of four islands: Puerto Rico, Cuba, Hispaniola, and Jamaica.[/hl:1] Moreover, the Puerto Rican twig species closely resembles the twig species of Cuba, Hispaniola, and Jamaica in morphology, habitat use, and behavior. Likewise, the spe- cialists for other habitats are similar across the islands.The presence of similar species on different islands could be variously explained. An ancestral species might have adapted to exploit a particular ecological niche on one island and then traveled over water to colonize other islands. Or this ancestral species might have evolved at a time when the islands were connected, which some of these islands may once have been. After the islands separated, the isolated lizard populations would have become distinct species while also retaining their ancestors' niche adaptations. Both of these scenarios imply that specialization to each niche occurred only once. Alternatively, each specialist could have arisen independently on each of the islands.If each type of specialist evolved just once, then similar specialists on different islands would be closely related. Conversely, if the specialists evolved independently on each island, then a specialist on one island would be more closely related to other types of anoles on the same island-regardless of their ecological niches- than it would be to a similar specialist on a different island.Biologists can infer how species are related evolutionarily by comparing DNA sequences for the same genes in different species. Species with similar DNA sequences for these genes are generally more closely related to each other than to species with less-similar DNA sequences. DNA evidence concerning the anoles led researchers to conclude that habitat specialists on one island are not closely related to the same habitat specialists elsewhere, indicating that specialists evolved independently on each island.
A small number of the forest species of lepidoptera (moths and butterflies, which exist as caterpillars during most of their life cycle) exhibit regularly recurring patterns of population growth and decline—such fluctuations in population are known as population cycles. Although many different variables influence population levels, a regular pattern such as a population cycle seems to imply a dominant, driving force. Identification of that driving force, however, has proved surprisingly elusive despite considerable research. The common approach of studying causes of population cycles by measuring the mortality caused by different agents, such as predatory birds or parasites, has been unproductive in the case of lepidoptera. Moreover, population ecologists' attempts to alter cycles by changing the caterpillars' habitat and by reducing caterpillar populations have not succeeded. [hl:1]In short, the evidence implies that these insect populations, if not self-regulating, may at least be regulated by an agent more intimately connected with the insect than are predatory birds or parasites.[/hl:1]Recent work suggests that this agent may be a virus.For many years, viral disease had been reported in declining populations of caterpillars, but population ecologists had usually considered viral disease to have contributed to the decline once it was underway rather than to have initiated it. The recent work has been made possible by new techniques of molecular biology that allow viral DNA to be detected at low concentrations in the environment. Nuclear polyhedrosis viruses are hypothesized to be the driving force behind population cycles in lepidoptera in part because the viruses themselves follow an infectious cycle in which, if protected from direct sun light, they may remain virulent for many years in the environment, embedded in durable crystals of polyhedrin protein. Once ingested by a caterpillar, the crystals dissolve, releasing the virus to infect the insect's cells. Late in the course of the infection, millions of new virus particles are formed and enclosed in polyhedron crystals. These crystals reenter the environment after the insect dies and decomposes, thus becoming available to infect other caterpillars.One of the attractions of this hypothesis is its broad applicability. Remarkably, despite significant differences in habitat and behavior, many species of lepidoptera have population cycles of similar length, between eight and eleven years. Nuclear polyhedrosis viral infection is one factor these disparate species share."
By the sixteenth century, the Incas of South America ruled an empire that extended along the Pacific coast and Andean highlands from what is now Ecuador to central Chile. While most of the Incas were self-sufficient agriculturists, the inhabitants of the highland basins above 9,000 feet were constrained by the kinds of crops they could cultivate. Whereas 95 percent of the principal Andean food crops can be cultivated below 3,000 feet, only 20 percent reproduce readily above 9,000 feet. Given this unequal resource distribution, highland Incas needed access to the products of lower, warmer climatic zones in order to enlarge the variety and quantity of their foodstuffs. [hl:1]In most of the preindustrial world, the problem of different resource distribution was resolved by long-distance trade networks over which the end consumer exercised little control.[/hl:1] Although the peoples of the Andean highlands participated in such networks, they relied primarily on the maintenance of autonomous production forces in as many ecological zones as possible. The commodities produced in these zones were extracted, processed, and transported entirely by members of a single group.This strategy of direct access to a maximum number of ecological zones by a single group is called vertical economy. Even today, one can see Andean communities maintaining use rights simultaneously to pasturelands above 12,000 feet, to potato fields in basins over 9,000 feet, and to plots of warm-land crops in regions below 6,000 feet. This strategy has two principal variations. The first is “compressed verticality,” in which a single village resides in a location that permits easy access to closely located ecological zones. Different crop zones or pasturelands are located within a few days walk of the parent community. Community members may reside temporarily in one of the lower zones to manage the extraction of products unavailable in the homeland. In the second variation, called the “vertical archipelago,” the village exploits resources in widely dispersed locations, constituting a series of independent production “islands.” In certain pre-Columbian Inca societies, groups were sent from the home territory to establish permanent satellite communities or colonies in distant tropical forests or coastal locations. There the colonists grew crops and extracted products for their own use and for transshipment back to their high-altitude compatriots. In contrast to the compressed verticality system, in this system, commodities rather than people circulated through the archipelago."
Before the age of space exploration, astronomers assumed that the Moon's core was smaller than the Earth's, in both relative and absolute terms – the radius of the Earth's core is 55 percent of the overall radius of the Earth and the core's mass is 32 percent of the Earth's overall mass – but they had no way to verify this. Two sets of data gathered by Lunar Prospector have now given astronomers the ability to determine that the Moon's core accounts for 20 percent of the Moon's radius and for a mere 2 percent of its overall mass.First, scientists measured minute, relatively rapid variations in the wavelength of radio signals from Lunar Prospector as the craft moved towards or away from the Earth. Using these variations, scientists accurately determined even slight changes in the craft's velocity while the craft orbited the Moon, changes resulting from inconsistency in the gravitational pull of the Moon on the craft. The data were used to create a [hl:1]"gravity map"[/hl:1] of both near and far sides of the Moon, highlighting new details of the distribution of the Moon's internal mass. Scientists thus determined that the Moon has a small, metallic core, which, if composed mostly of iron, has a radius of approximately 350 kilometers. The second method involved examining the faint magnetic field generated within the Moon itself by the Moon's monthly passage through the tail of the Earth's magnetosphere. This approach confirmed the results obtained through examination of the gravity map. The size and composition of the Moon's core have serious implications for our understanding of the Moon's origins. If the Moon and Earth developed as distinct entities, the sizes of their cores should be more comparable. In actuality, it seems that the Moon was once part of the Earth and broke away at an early stage in the Earth's evolution, perhaps due to a major asteroid impact that could have loosened a chunk of iron, allowing it to form the core around which the Moon eventually coalesced. Alternatively, according to fission theory, the early Earth may have spun so rapidly that it ejected a quantity of material by [hl:2]so-called[/hl:2] centrifugal force, material that later coalesced by mutual gravitational attraction into the Moon.
Ready4

The shaded portion of the rectangle shown above represents a piece that will be cut from a tile to fit into a mosaic. If the area of the shaded portion is 21 square centimeters and , then equals
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The evolutionary theory of punctuated equilibrium maintains that the characteristics that are possessed by any given species developed over long periods of stability interrupted by short periods of rapid change.
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In the famous thought experiment that inspired the theory of relativity, Einstein asked himself whether a beam of light would look the same to an observer moving alongside the beam at the same speed as an observer who was stationary.
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Assuming that the new drug is approved, it will remain to be seen whether it decreases post-traumatic stress disorder in military veterans after it is widely administered.
OG15 OG16 OG17 The following appeared in a speech by a stockholder of Consolidated Industries at the company's annual stockholders' meeting:"In the computer hardware division last year, profits fell significantly below projections, the product line decreased from 20 to only 5 items, and expenditures for employee benefits increased by 15 percent. Nevertheless, Consolidated's board of directors has approved an annual salary of more than $1 million for our company's chief executive officer. The present board members should be replaced because they are unconcerned about the increasing costs of employee benefits and salaries, in spite of the company's problems generating income."Discuss how well reasoned you find this argument. In your discussion be sure to analyze the line of reasoning and the use of evidence in the argument. For example, you may need to consider what questionable assumptions underlie the thinking and what alternative explanations or counterexamples might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would make it more logically sound, and what, if anything, would help you better evaluate its conclusion.
OG15 OG16 OG17 The following appeared in a memorandum from the business planning department of Avia Airlines:"Of all the cities in their region, Beaumont and Fletcher are showing the fastest growth in the number of new businesses. Therefore, Avia should establish a commuter route between them as a means of countering recent losses on its main passenger routes. And to make the commuter route more profitable from the outset, Avia should offer a 1/3 discount on tickets purchased within two days of the flight. Unlike tickets bought earlier, discount tickets will be nonrefundable, and so gain from their sale will be greater."Discuss how well reasoned you find this argument. In your discussion be sure to analyze the line of reasoning and the use of evidence in the argument. For example, you may need to consider what questionable assumptions underlie the thinking and what alternative explanations or counterexamples might weaken the conclusion. You can also discuss what sort of evidence would strengthen or refute the argument, what changes in the argument would make it more logically sound, and what, if anything, would help you better evaluate its conclusion.
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The number of gray whales spotted migrating south off the Southern California coast was 364 in December, prompting uncertainty as to whether the population of the endangered species actually doubled that of the 20,000 estimate of the previous year.
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A new law proposed by privacy advocates would increase the amount of tint that carmakers have been allowed to build into the windows of their vehicles.
Javier rates his work-readiness on a scale from 0 to 10 points, with 10 being maximum readiness. He wants his rating to be as high as possible when he arrives at his office and has found that the rating is affected by how late he sleeps and how long he spends preparing for work. His alarm clock sounds at 6 a.m., at which time he has a work-readiness rating of 10. He needs to leave for work at exactly 6:40 am. During these 40 minutes, Javier's only activities are sleeping or preparing for work.If Javier spends more than 25 minutes or less than 10 minutes to prepare, his rating is reduced by 5 points. To sleep past 6 a.m., however, Javier must use the snooze button on his alarm clock, which delays the alarm by 4 minutes. Each press of the snooze button after the third will decrease Javier's efficiency rating by 1 point.In the following table, select for rating the greatest work-readiness rating that Javier can achieve and select for Snoozes the number of times he must press the snooze button to achieve that rating. Make only two selections, one in each column.
A literature department at a small university in an English-speaking country is organizing a two-day festival in which it will highlight the works of ten writers who have been the subjects of recent scholarly work by the faculty. Five writers will be featured each day. To reflect the department's strengths, the majority of writers scheduled for one of the days will be writers whose primary writing language is not English. On the other day of the festival, at least four of the writers will be women. Neither day should have more than two writers from the same country. Departmental members have already agreed on a schedule for eight of the writers. That schedule showing names, along with each writer's primary writing language and country of origin, is shown. Day 1:Achebe (male, English, Nigeria)Weil (female, French, France)Gavalda (female, French, France)Barrett Browning (female, English, UKDay 2:Rowling (female, English, UK)Austen (female, English, UK)Ocantos (male, Spanish, Argentina)Lu Xun (male, Chinese, ChinSelect a writer who could be added to the schedule for either day. Then select a writer who could be added to the schedule for neither day. Make only two selections, one in each column.
Ready4 Thanks to advances in science and technology, many people that might at one time have been crippled as children by diseases such as poliomyelitis or Charcot-Marie-Tooth disease now enjoy near-normal lifestyles.
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It is not in fact a whale, but the whale shark is as large as some species of whales, which measures up to 42 feet from tooth to fin.