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What are the two speakers talking about
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Text 4 To us, it seems so natural to put up an umbrella to keep the water off when it rains. But actually the umbrella was not invented as protection against rain. Its first use was as a shade against the sun. Nobody knows who first invented it, but the umbrella was used in very ancient times. Probably the first to use it were the Chinese, way back in the 1th century B.C. We know that the umbrella was used in ancient Egypt and Babylon as a sunshade. And there was a strange thing connected with its use: it became a symbol of honor and authority. In the Far East, in ancient times, the umbrella was allowed to be used only by royalty or by those in high office. In Europe, the Greeks were the first to use the umbrella as a sunshade. And the umbrella was in common use in ancient Greece. But it is believed that the first persons in Europe to use the umbrella as protection against the rain were the ancient Romans. During the Middle Ages, the use of the umbrella practically disappeared. Then it appeared again in Italy in the late sixteenth century. And again it was considered a symbol of power and authority. By 1680, the umbrella appeared in France, and later on in England. By the eighteenth century, the umbrella was used against rain throughout most of Europe. Umbrellas have not changed much in style during all this time, though they have become much lighter in weight. It was not until the twentieth century that women’ s umbrella began to be made, in a whole variety of colors. A strange feature of the umbrella’s use is that it was used as ______.
患儿，女，6岁，不规则发热1月余，，伴关节肿痛，四肢有环形红斑出现，为明确诊断而就诊，请问以下哪项实验室检查对诊断没有意义
The molecules of carbon dioxide in the Earth’s atmosphere affect the heat balance of the Earth by acting as a one-way screen. (1) these molecules allow radiation at visible wavelengths, where most of the energy of sunlight is concerned, to pass (2) , they absorb some of the longer-wave-length, infrared emissions radiated from the Earth’s surface, radiation that would (3) be transmitted back into space. For the Earth to maintain a constant average temperature, such emissions from the planet must (4) incoming solar radiation. If there were no carbon dioxide in the atmosphere, heat would (5) from the Earth much more easily.Today, (6) , the potential problem is too much carbon dioxide. Could the increase in carbon dioxide (7) a global rise in average temperature, and could such a rise have serious (8) for human society Mathematical models that allow us to calculate the rise in temperature as a function of the increase (9) ;that the (10) is probably yes.One mathematical model (11) that doubling the atmospheric carbon dioxide would raise the global mean surface temperature by 2.5℃. This model assumes that the atmosphere’s relative humidity remains constant and the temperature decreases with altitude at a (12) of 6.5℃ per kilometer. The assumption of constant relative humidity is important, because water vapor in the atmosphere is another (13) absorber or radiation at infrared wavelengths. Because warm air can hold more (14) than cool air, the relative humidity will be constant (15) the amount of water vapor in the atmosphere increases (16) the temperature rises. (17) , more infrared radiation would be absorbed and reradiated (18) to the Earth’s surface. The resultant warming at the surface could be expected to melt snow and ice, (19) the Earth’s reflectivity. More solar radiation would be absorbed, (20) to a further increase in temperature. Read the following text. Choose the best word (s) for each numbered blank and mark A, B, C or D on ANSWER SHEET 1.16（）
阅读下面这篇短文，短文后列出了7个句子，清根据短文的内容对每个句子作出判断。如果该句提供的是正确信息，请选择A项；如果该句提供的是错误信息，请选择B项；如果该句的信息文章中没有提及，请选择C项。 Plants in Desert Only special plants can survive the terrible climate of a desert, for these are regions when the annual range of the soil temperature can be over 75℃. Furthermore, during the summer there are few clouds in the sky to protect plans from the sun’ s ray. Another problem is the fact that there are frequently strong winds that drive small, sharp particles of sand into the plants,earing and damaging them. The most difficult probiem for all forms of plant life, however, is the fact that the entire annual rainfall occurs during a few days or weeks in spring. Grasses and flowers in desert survive from one year to the next by existing through the long, hot, dry season in the form of seeds. These seeds remain inactive unless the fight amount of’rain falls. If no rain falls, or if insufficient rain falls, they wait until the next year, or even still the next. Another factor that helps these plants to survive is the fact that their life cycles are short. By the time the water from the spring rains disappears — just a few weeks after it falls — such plants no longer need any. The perennials (多年生植物) have special features that enable them to survive as plants for several years. Thus, nearly all desert perennials have extensive root systems below ground and a small shoot system above ground. The large root network enables the plant to absorb as much water as possible in short time. The small shoot system, on the other hand, considerably limits water loss by evaporation. Another feature of many perennials is that after the rainy season they 10se their leaves in preparation for the long, dry season, just as trees in wetter climates lose theirs in preparation for the winter. This reduces their water loss by evaporation (蒸发) duing the dry season. Then, in next rainy season, they come fully alive once more, and grow new branches, leaves and flowers, just as the grasses and flowers in desert do. The shoot system of perennials can help the plants absorb less of the sun’ s ray.
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