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卫生注册证书和卫生登记证书有效期3年。( )
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出口预包装仪器报检的特殊要求是经营者或其代理人在出口仪器前应当向指定的检验检疫机构提出仪器标签审核申请，获得《进出口食品标签审核证书》或《标签审核受理证明》方可获得报检手续。( )
测得值与真值接近的程度
Because the low latitudes of the Earth, the areas near the equator, receive more heat Than the latitudes near the poles, and because the nature of heat is to expand and move, Heat is transported from the tropics to the middle and high latitudes. Some of this heat is Moved by winds and some by ocean currents, and some gets stored in the atmosphere in(5) the form of latent heat. The term "latent heat" refers to the energy that has to be used to Convert liquid water to water vapor. We know that if we warm a pan of water on a stove, it will evaporate, or turn into vapor, faster than if it is allowed to sit at room temperature. We also know that if we hang wet clothes outside in the summertime they will dry faster than in winter, when temperatures are colder. The energy used in both cases to change (10) liquid water to water vapor is supplied by heat―supplied by the stove in the first case and by the Sun in the latter case. This energy is not lost. It is stored in water vapor in the atmosphere as latent heat. Eventually, the water stored as vapor in the atmosphere will condense to liquid again, and the energy will be released to the atmosphere. In the atmosphere, a large portion of the Sun’’s incoming energy is used to evaporate (15) Water, primarily in the tropical oceans. Scientists have tried to quantify this proportion of the Sun’’s energy. By analyzing temperature, water vapor, and wind data around the globe, they have estimated the quantity to be about 90 watts per square meter, or nearly 30 percent of the Sun’’s energy. Once this latent heat is stored within the atmosphere, it can be transported, primarily to higher latitudes, by prevailing, large-scale winds. Or it (20) can be transported vertically to higher levels in the atmosphere, where it forms clouds and subsequent storms, which then release the energy back to the atmosphere. All of the following words are defined in the passage EXCEPT
Many prehistoric people subsisted as hunters and gatherers. Undoubtedly, game animals, including some very large species, provided major components of human diets. An important controversy centering on the question of human effects on prehistoric wildlife concerns the sudden disappearance of so many species of large animals at or near the end(5) of the Pleistocene epoch. Most paleontologists suspect that abrupt changes in climate led to the mass extinctions. Others, however, have concluded that prehistoric people drove many of those species to extinction through over-hunting. In their "Pleistocene overkill hypothesis," they cite what seems to be a remarkable coincidence between the arrival of prehistoric peoples in North and South America and the time during which mammoths,(10) giant ground sloths, the giant bison, and numerous other large mammals became extinct. Perhaps the human species was driving others to extinction long before the dawn of history. Hunter-gatherers may have contributed to Pleistocene extinctions in more indirect ways. Besides over-hunting, at least three other kinds of effects have been suggested: direct competition, imbalances between competing species of game animals, and early(15) agricultural practices. Direct competition may have brought about the demise of large carnivores such as the saber-toothed cats. These animals simply may have been unable to compete with the increasingly sophisticated hunting skills of Pleistocene people. Human hunters could have caused imbalances among game animals, leading to the extinctions of species less able to compete. When other predators such as the gray wolf(20) prey upon large mammals, they generally take high proportions of each year s crop of young. Some human hunters, in contrast, tend to take the various age-groups of large animals in proportion to their actual occurrence. If such hunters first competed with the larger predators and then replaced them. they may have allowed more young to survive each year, gradually increasing the populations of favored species As these populations expanded,(25) they in turn may have competed with other game species for the same environmental niche, forcing the less hunted species into extinction. This theory, suggests that human hunters played an indirect role in Pleistocene extinctions by hunting one species more than another. According to the passage, what is one difference between the hunting done by some humans and the hunting done by gray wolves
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