Which of the following most logically completes the passage?
Which of the following, if true, most helps to resolve the status of the orbiting body without casting doubt on the two standard theories mentioned?
Which of the following, if true in Gilavia, most strongly supports the proposed explanation?
The passage suggests that which of the following is frequently true of the title pages of early-nineteenth-century English novels?
The passage is primarily concerned with
Even after numerous products made with artificial sweeteners became available, sugar consumption per capita continued to rise. Now manufacturers are introducing fat-free versions of various foods that they claim have the taste and texture of the traditional high-fat versions. Even if the manufacturers' claim is true, given that the availability of sugar-free foods did not reduce sugar consumption, it is unlikely that the availability of these fat-free foods will reduce fat consumption.
Which of the following, if true, most seriously undermines the argument?
Recent studies of sediment in the North Atlantic's deep waters reveal possible cyclical patterns in the history of Earth's climate. The rock fragments in these sediments are too large to have been transported there by ocean currents, they must have reached their present locations by traveling in large icebergs that floated long distances from their point of origin before melting. Geologist Gerard Bond noticed that some of the sediment grains were stained with iron oxide, evidence that they originated in locales where glaciers had overrun outcrops of red sandstone. Bond's detailed analysis of deep-water sediment cores showed changes in the mix of sediment sources over time: the proportion of these red-stained grains fluctuated back and forth from lows of 5 percent to highs of about 17 percent, and these fluctuations occurred in a nearly regular 1,500-year cycle.

Bond hypothesized that the alternating cycles might be evidence of changes in ocean-water circulation and therefore in Earth's climate. He knew that the sources of the red-stained grains were generally closer to the North Pole than were the places yielding a high proportion of “clean” grams. At certain times, apparently, more icebergs from the Arctic Ocean in the far north were traveling south well into the North Atlantic before melting and shedding their sediment.

Ocean waters are constantly moving, and water temperature is both a cause and an effect of this movement. As water cools, it becomes denser and sinks to the ocean's bottom. During some periods, the bottom layer of the world's oceans comes from cold, dense water sinking in the far North Atlantic. This causes the warm surface waters of the Gulf Stream to be pulled northward. Bond realized that during such periods, the influx of these warm surface waters into northern regions could cause a large proportion of the icebergs that bear red grains to melt before traveling very far into the North Atlantic. But sometimes the ocean's dynamic changes, and waters from the Gulf Stream do not travel northward in this way. During these periods, surface waters in the North Atlantic would generally be colder, permitting icebergs bearing red-stained grains to travel farther south in the North Atlantic before melting and depositing their sediment.

The onset of the so-called Little Ice Age (1300-1860),which followed the Medieval Warm Period of the eighth through tenth centuries, may represent the most recent time that the ocean's dynamic changed in this way. If ongoing climate-history studies support Bond's hypothesis of 1,500-year cycles, scientists may establish a major natural rhythm in Earth's temperatures that could then be extrapolated into the future. Because the midpoint of the Medieval Warm Period was about AD. 850, an extension of Bond's cycles would place the midpoint of the next warm interval in the twenty-fourth century.
According to the passage, which of the following is true of the rock fragments contained in the sediments studied by Bond?
Historians frequently employ probate inventories——lists of possessions compiled after a person's death—to estimate standard of living. Because these inventories were taken by amateur assessors according to unwritten rules, they are sometimes unreliable. One way to check their accuracy is to compare them to archaeological records. A study of records from the state of Delaware in the eighteenth century found that while very few inventories listed earthenware, every excavation contained earthenware. Earthenware may have gone unlisted simply because it was inexpensive. But if it was so commonplace, why was it listed more often for wealthy households? Perhaps the more earthenware people had, the more likely appraisers were to note it. A few bowls could easily be absorbed into another category, but a roomful of earthenware could not.
Select the sentence that provides support for an answer to a question in the passage.
In the 1980s, neuroscientists studying the brain processes underlying our sense of conscious will compared subjects' judgments regarding their subjective will to move (W) and actual movement (M) with objective electroencephalographic activity called readiness potential, or RP. As expected, W preceded M: subjects consciously perceived the intention to move as preceding a conscious experience of actually moving. This might seem to suggest an appropriate correspondence between the sequence of subjective experiences and the sequence of the underlying events in the brain. But researchers actually found a surprising temporal relation between subjective experience and objectively measured neural events: in direct contradiction of the classical conception of free will, neural preparation to move (RP) preceded conscious awareness of the intention to move (W) by hundreds of milliseconds.
Based on information contained in the passage, which of the following chains of events would most closely conform to the classical conception of free will?
Ram-soaked soil contains less oxygen than does drier soil.The roots of melon plants perform less efficiently under the lowoxygen conditions present in rain-soaked soil. When the efficiency of melon roots is impaired, the roots do not supply sufficient amounts of the proper nutrients for the plants to perform photosynthesis at their usual levels. It follows that melon plants have a lower-than-usual rate of photosynthesis when their roots are in rain-soaked soil. When the photosynthesis of the plants slows, sugar stored in the fruits is drawn off to supply the plants with energy. Therefore, ripe melons harvested after a prolonged period of heavy rain should be less sweet than other ripe melons.
In the argument given, the two portions in boldface play which of the following roles?
In Raisin in the Sum, Lorraine Hansberry does not reject integration or the economic and moral promise of the American dream; rather, she remains loyal to this dream while looking, realistically, at its incomplete realization. Once we recognize this dual vision, we can accept the play's ironic nuances as deliberate social commentaries by Hansberry rather than as the “unintentional" irony that Bigsby attributes to the work. Indeed, a curiously persistent refusal to credit Hansberry with a capacity for intentional irony has led some critics to interpret the play's thematic conflictsas mere confusion, contradiction, or eclecticism. Isaacs, for example, cannot easily reconcile Hansberry's intense concern for her race with her ideal of human reconciliation. But the play's complex view of Black self-esteem and human solidarity as compatible is no more “contradictory" than Du Bois' famous, well-considered ideal of ethnic self-awareness coexisting with human unity, or Fanon's emphasis on an ideal internationalism that also accommodates national identities and roles.
The author of the passage would probably consider which of the following judgments to be most similar to the reasoning of the highlighted critics?
Objectively, of course, the various ecosystems that sustain life on the planet proceed independently of human agency, just as they operated before the hectic ascendancy of Homo sapiens. But it is also true that it is difficult to think of a single such system that has not, for better or worse, been substantially modified by human culture. Nor is this simply the work of the industrial centuries. It has been happening since the days of ancient Mesopotamia. It is coeval with the origins of writing, and has occurred throughout our social existence. And it is this irreversibly modified world, from the polar caps to the equatorial forests, that is all the nature we have.
It can be inferred from the passage that the author would agree with which of the following statements?
The nearly circular orbits of planets in our solar system led scientists to expect that planets around other stars would also reside in circular orbits. However, most known extrasolar planets reside in highly elongated, not circular, orbits. Why? The best clue comes from comets in our solar system. Comets formed in circular orbits but were gravitationally flung into their present-day elliptical orbits when they ventured too close to planets. Astronomers suspect that pairs of planets also engage in this slingshot activity, leaving them in disturbed, elliptical orbits. If two planets form in close orbits, one will be scattered inward(toward its star), the other outward. They will likely then travel close enough to neighboring planets to disturb their orbits also.


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