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“知之为知之，不知为不知，是知也”一句中的最后一个“知”字应解释为()
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“一部力透纸背，情透纸背，热透纸背”的“讲真话”的书是指散文集()
下列文章选自《汉书》的是 ()
Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D. (40 points)
The origin of continental nuclei has long been a puzzle. Theories advanced so far have generally failed to explain the first step in continent growth, or have been subject to serious objections. It is the purpose of this article to examine the possible role of the impact of large meteorites or asteroids in the production of continental nuclei. Unfortunately, the geological evolution of the Earth's surface has had an obliterating effect on the original composition and structure of the continents to such an extent that further terrestrial investigations have small chance of arriving at an unambiguous answer to the question of continental origin. Paradoxically, clues to the origin and early history of the surface features of the Earth may be found on the Moon and planets, rather than on the Earth, because some of these bodies appear to have had a much less active geological history. As a result, relatively primitive surface features are preserved for study and analysis. In the case of both the Moon and Mars, it is generally concluded from the appearance of their heavily cratered surfaces that they have been subjected to bombardment by large meteoroids during their geological history. Likewise, it would appear a reasonable hypothesis that the Earth has also been subjected to meteoroid bombardment in the past, and that very large bodies struck the Earth early in its geological history.
The largest crater on the Moon listed by Baldwin has a diameter of 285 km. However, if we accept the hypothesis of formation of some of the mare basins by impact, the maximum lunar impact crater diameter is probably as large as 650 km. Based on a lunar analogy, one might expect several impact craters of at least 500 km diameter to have been formed on Earth. By applying Baldwin's equation, the depth of such a crater should be about 20 km. Baldwin admits that his equation gives excessive depths for large craters so that the actual depth should be somewhat smaller. Based on the measured depth of smaller lunar craters, a depth of 10 km is probably a conservative estimate for the diameter of a 500 km impact crater. Baldwin's equation gives the depth of the zone of brecciation for such a crater as about 75 km. The plasticity, of the Earth's mantle at the depth makes it impossible to speak of "brecciation" in the usual sense. However, local stresses may be temporarily sustained at that depth, as shown by the existence of deep-focus earthquakes. Thus, short-term effects might be expected to a depth of more than 50 km in the mantle.
Even without knowing the precise effects, there is little doubt that the formation of a 500 km crater would be a major geological event. Numerous authors have considered the geological implications of such an event. Donn et al. have, for example, called on the impact of continent-size bodies of sialic composition to form. the original continents. Two major difficulties inherent in this concept are the lack of any known sialic meteorites, and the high probability that the energy of impact would result in a wide dissemination of sialic material, rather than its concentration at the point of impact.
Gilvarry, on the other hand, called on meteoroid impact to explain the production of ocean basins. The major difficulties with this model are that the morphology of most of the ocean basins is not consistent with impact, and that the origin and growth, of continents is not adequately explained.
We agree with Donn et al. that the impact of large meteorites or asteroids may have caused continent formation, but would rather think in terms of the localized addition of energy to the system, rather than in terms of the addition of actual sialic material.
A mare basin is______.
The crucial question, however, about the restorationist outlook has to do with the degree to which the restorationist program is itself faithful to the first principle of restoration: that nature and humanity are fundamentally united rather than separate. Rejecting the old domination model, which sees humans as over nature, restoration theory supports a model of community participation. Yet some of the descriptions that Jordan and Turner give of what restorationists are actually up to—for example, Turner's description of humans as "the lords of creation", or Jordan's statement that "the fate and well being of the biosphere depend ultimately on us and our relationship with it"—are not consistent well with the community—participation model.
Another holistic model namely, that of nature as an organism—might be more serviceable to the restorationists. As with the community model, the "organic" model pictures nature as a system of interconnected parts. A fundamental difference, however, is that in an organism the parts are wholly useful to the life of the organism. If we could think of the biosphere as a single living organism and could identify humans with the brain (or the DNA), or control center, we would have a model that more closely fits the restorationists view.
However, to consider humans as the control center of the living earth is to attribute to them a dominating role in nature. Is this significantly different from the old-fashioned domination model？ In both systems humans hold the place of highest authority and power in the world. Also neither view recognizes any limits to the scope and range of reasonable human manipulation in the world. This does not mean that there are no restrictions, only beneficial manipulation, should be undertaken. But it does not mean that nothing is off-limits. A further parallel is that, because the fate of the world rests on humans, they must have a clear idea of what needs to be done. There are also important differences between the two theories. For example, restorationists no longer view the world in the old dominationist way as a passive object. And though both assign to humans a controlling role in the world, dominationists conceive this in terms of conquest while restorationists conceive it in terms of healing. Also, restorationists insist that the ideas which must serve to guide our work in the world are drawn not solely from a consideration of human needs and purposes but from an understanding of the biosphere; as a result, they are more conscious than dominationists of our capacity to human nature.
The author would probably agree that preservationists______.
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