哪种A/T方式允许人工调整推力而不受A/T的影响()?A、速度和预位 B、N1和预位

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问题:

哪种A/T方式允许人工调整推力而不受A/T的影响()?

A、速度和预位

B、N1和预位

C、推力保持和预位

D、复飞和预位

考点:民用航空器维修执照考试737NG机型737NG机型题库
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学习权

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(二)
材料一 煤炭是我国最安全、最经济、最可靠的能源。我国能源资源的基本特点决定了煤炭在一次能源中的重要地位。我国煤炭资源总量远远超过石油和天然气资源;我国煤炭资源总量为5.6万亿吨,其中已探明储量为1万亿吨,占世界总储量的11%。(石油占2.4%,天然气占1.2%)
材料二 中国能源30%依赖石油,而30%的石油需要进口。中国现在是世界上第二大能源消费国,也是第二大石油进口国。专家预测,到2020年,我国石油需求将达4.3亿吨,而届时中国的石油产量只有2亿吨,对外依存度达60%。
材料三 由于世界能源的短缺和环境保护的需要,醇类燃料是自20世纪70年代以来成为新能源开发的方向之一。车用乙醇汽油是在加入一定比例的变性燃料乙醇后调配成的一种新型清洁车用燃料。变性燃料乙醇是以玉米、小麦、薯类、甘蔗、甜菜等为原料,经发酵、蒸馏制得乙醇,脱水后再添加变性剂变性的燃料乙醇。经国务院批准,自2002年6月30日起,郑州、洛阳、南阳、哈尔滨、肇东5个城市,开展了为期1年的车用乙醇汽油试点工作,在试点成功的基础上,把试点范围扩大到黑龙江、吉林、辽宁、河南、安徽5省及湖北、山东、河北和江苏4省的部分地区,到2005年底上述地区基本实现车用乙醇汽油代替其他汽油。

根据材料,我国能源资源的特点有( )。

A.富煤

B.贫油

C.少气

D.新能源丰富

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Few creatures on earth are as cute as the black lion tamarin, and few have as dramatic a story line. Pug-nosed and diminutive, with a comic fringe of hair, these monkeys dwell in trees in small tracts of forest in southeastern Brazil. Or they did until 1905, when they were declared extinct. No one saw a black lion tamarin again in the wild until 1970. Later, in the 1990s, some Brazilian researchers turned up a small set of isolated, inbred populations scattered over a wide region. Since that time, they have been engineering tamarin migration, doing everything they can to save the world’s most distinctive primates.
Although they are no larger than house cats, tamarins have brains big for their size and a family life organized like our own. They live in groups anchored by an adult male andadult female, along with their offspring. When a mother bears young, she usually produces twins, and although members of the group share in their upbringing, it is most often the father who carries them around in the trees, where the families feed on fruits, insects and bird’s eggs.
Unhappily for the lion tamarins, their tree-bound niche began to disappear after the Portuguese landed in Brazil and began clearing forest to make room for Rio de Janeiro, the settlements and farms. As is the case for so many threatened species, the breakup of their habitat sounded the death knell for tamarins, depriving them of the continuity of forest they require to remain abundant and safe from potential threats in any single vicinity. The animals avoid predators by hardly ever coming down from the trees, so even a narrow logging road through a forest can begin the breakup by preventing them from moving from one patch of forest to another.
A simple solution was to build bridges across roads, allowing the monkeys to move from one forest to another. With some lumber and the researchers’ work, habitats that had been separated became continuous again, improving opportunities for migrating and mating.
The next step was to broaden the distribution of the population. The researchers captured two families of black lion tamarins and moved them to a new forest. After a year, the moves were declared a success: Not only had 80 percent of the tamarins survived, but they had also produced new offspring. So far, so good. The researchers had learned the animals could adjust to the new habitats, even if the insects there tasted a little different or the trees were a slightly different size.
The techniques for saving species in the wild vary. Species with less stringent habitat requirements, like wild turkeys, have been rescued by moving them into new settings as well as outlawing their killing. More challenging to preserve are species that require a lot of land, like elephants, and species that have highly specific requirements for habitat and prey -- like black-footed ferrets. Ultimately, as in all challenges, knowledge is power to save wild species from extinction.

A tamarin can be called any of the following EXCEPT ______.

A.a monkey

B.a primate

C.a house cat

D.a lion tamarin

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发展旺盛的积雨云顶部呈砧状,这是由于()造成的。

A.高空急流

B.高空气温过低

C.对流层顶存在逆温层

D.空气湿度过小

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阶梯状断层

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