总温传感器电加温防冰用的是()A.28VDC; B.115VAC。

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问题:

总温传感器电加温防冰用的是()

A.28VDC;

B.115VAC。

考点:民用航空器维修执照考试A320系列飞机MEA320系列飞机ME题库
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个人财务报表与企业财务报表的区别主要有()。

A.个人及家庭的财务报表,不受会计准则的要求

B.个人及家庭财务报表信息大部分情况下都不需要对外公开

C.个人及家庭的财务报表不必对资产计提折旧资产多以原值填列

D.企业财务报表中资产负债表与利润表中所必需的对应关系在个人及家庭财务报表中显得不是那么重要

E.在个人及家庭的财务管理中理财规划师倾向于处理将来会有的收入而不是现金

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In almost all cases the soft parts of fossils are gone for ever but they were fitted around or within the hard parts. Many of them also were attached to the hard parts and usually such attachments are visible as depressed or elevated areas, ridges, or grooves, smooth or rough patches on the hard parts. The muscles most important for the activities of the animal and most evident in the appearance of the living animal are those attached to the hard parts and possible to reconstruct from their attachments. Much can be learned about a vanished brain from the inside of the skull in which it was lodged.
Restoration of the external appearance of an extinct animal has little or no scientific value. It does not even help in inferring what the activities of the living animal were, how fast it could run, what its food was, or such other conclusions as are important for the history of life. However, what most people want to know about extinct animals is what they looked like when they were alive. Scientists also would like to know. Things like fossil shells present no great problem as a rule, because the hard parts are external when the animal is alive and the outer appearance is actually preserved in the fossils.
Animals in which the skeleton is internal present great problems of restoration, and honest restorers admit that they often have to use considerable guessing. The general shape and contours of the body are fixed by the skeleton and by muscles attached to the skeleton, but surface features, which may give the animal its really characteristic look, are seldom restorable with any real probability of accuracy. The present often helps to interpret the past. An extinct animal presumably looked more or less like its living relatives, if it has any. This, however, may be quite equivocal. For example, extinct members of the horse family are usually restored to look somewhat like the most familiar living horses — domestic horses and their closest wild relatives. It is, however, possible and even probable that many extinct horses were striped like zebras. Others probably had patterns no longer present in any living members of the family. If lions and tigers were extinct they would be restored to look exactly alike. No living elephants have much hair and mammoths, which are extinct elephants, would doubtless be restored as hairless if we did not happen to know that they had thick, woolly coats. We know this only because mammoths are so recently extinct that prehistoric men drew pictures of them and that the hide and hair have actually been found in a few specimens. For older extinct animals we have no such clues.

The reconstruction of a fossilized animal’s external appearance is considered necessary in order to______.

A.(A) satisfy popular curiosity

B.(B) answer scientific questions

C.(C) establish its activities

D.(D) determine its eating habits

题型:单项选择题

关于碱金属元素的下列叙述中,正确的是  [ ]

A.单质与水反应都能生成碱和H2

B.单质在空气中燃烧都生成过氧化物

C.单质都是质软、熔点低、密度均小于1的轻金属

D.单质依Li、Na、K、Rb、Cs的顺序熔沸点升高,密度增大

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银灰色地膜在生产中的主要作用是()。

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影,是日常生活中常见的光学现象。如:在墙壁上形成的手影;在湖水中亭子的倒影;用照相机摄影;电影院里的电影等等。下列知识对应正确的是()

A.手影——光的反射

B.水中倒影——光的直线传播

C.摄影——光的折射

D.看电影——光的镜面反射

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