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There is one passage in this section with 5 statements. Go over the passage quickly and answer the questions on the Answer Sheet. For questions 1-5, mark Y (for YES) if the statement agrees with the information given in the passage; N (for NO) if the statement contradicts the information given in the passage; NG (for NOT GIVEN) if the information is not given in the passage. When was the last time you saw a frog? Chances are, if you live in a city, you have not seen one for some time. Even in wet areas once teeming with frogs and toads, it is becoming less and less easy to find those slimy, hopping and sometimes poisonous members of the animal kingdom. All over the world, even in remote jungles on the far side of the globe, frogs are losing the ecological battle for survival, and biologists are at a loss to explain their demise. Are amphibians simply over-sensitive to changes in the ecosystem? Could their rapid decline in numbers be signalling some coming environmental disaster for us all? This frightening scenario is in part the consequence of a dramatic increase over the last quarter of a century in the development of once natural areas of wet marshland: home not only to frogs but to all manner of wildlife. Yet, there are no obvious reasons why certain frog species are disappearing from rainforests in the Southern Hemisphere which are barely touched by human hands. The mystery is unsettling to say the least, for it is known that amphibian species are extremely sensitive to environmental variations in temperature and moisture levels. The danger is that planet Earth might not only lose a vital link in the ecological food chain (frogs keep populations of otherwise pestilent insects at manageable levels), but we might be increasing our output of air pollutants to levels that may have already become irreversible. Frogs could be inadvertently warning us of a catastrophe. An example of a bizarre occurrence regarding a species of frog dates from the summer of 1995, when “an explosion” of multi-coloured frogs of the species Rana klepton esculenta occurred in the Netherlands. Normally these frogs are brown and greenish-brown, but some unknown contributory factor is turning these frogs yellow and / or orange. Nonetheless, so far, the unusual bi- and even tri-coloured frogs are functioning similarly to their normal-skinned contemporaries. It is thought that frogs with lighter coloured skins might be more likely to survive in an increasingly warm climate due to global warming. One theory put forward to explain extinct amphibian species that seems to fit the facts concerns the depletion of the ozone layer, a well-documented phenomenon which has led to a sharp increase in ultraviolet radiation levels. The ozone layer is meant to shield the Earth from UV rays, but increased radiation may be having a greater effect upon frog populations than previously believed. Another theory is that worldwide temperature increases are upsetting the breeding cycles of frogs. Statements: 1．Biologists are unable to explain why frogs are dying out. 2．Attempts are being made to halt the development of wet marshland. 3．Frogs are important in the ecosystem because they control pests. 4．It is not known why Dutch frogs are changing colour. 5．It is a fact that frogs’ breeding cycle has been upset by worldwide increases in temperature.
可促进肾小管钠重吸收的是（）
在三投影面体系中，若物体上的直线平行于侧立面而倾斜于另外两个投影面，则该直线为（），在（）投影为反映实长的斜线。
用TV-C-25代表25寸彩色电视机，这个代码属于（）
双块式无砟轨道道床板混凝土初凝后应立即解开（），（）等固定装置，释放钢轨（）应力。
在oracle联机事务数据库中不能提高查询性能的措施是 （）
梗阻性黄疸的主要影响应除外下列哪项：（）
沥青路面的（）的控制包括压路机的配置（台数、吨位及机型）、排列和碾压方式、压路机与摊铺机的距离、碾压温度、碾压速度、压路机洒水（雾化）情况、碾压段长度、调头方式等。
正常止血过程决定于以下哪几个因素（）
在评价未更正错报的影响时，注册会计师的判断正确的有（ ）。
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Heart（）
虎斑心（tigroid heart）
W: Coffee? M: No, thanks. I’m trying ______. It’s bad for my heart.
W: Coffee? M: No, thanks. I’m trying ______. It’s bad for my heart.
心衰细胞（heart failure cell）
W: Coffee? M: No, thanks. I’m trying ______. It’s bad for my heart.
心衰细胞（heart failure cell）
It took her a long while to recover（）her heart operation.
It took her a long while to recover（）her heart operation.
Mortality rates from heart disease and strokes in the United States have fallen ...