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问题 单项选择题

起落架收上过程中，收放作动筒的活塞杆（）

A.伸出

B.缩入

C.静止

D.先缩入，后伸出

答案

参考答案：A

填空题

Part 4


Questions 26-45


·Read the following passage and decide which answer best fits each space.
·Forquestions26-45, markoneletterA, B, C or D on the Answer Sheet.
Both (26) and zoology are parts of a more general field of science, biology. The two are studies of (27) things, which share certain characteristics, (28) they are plants or animals. Botany deals with plants, whose organisms that can (29) their own food by the use of sunlight. Zoology on (30) hand, deals with animals, those organisms that cannot manufacture their own food and are thus dependent (31) plants for their food.
(32) plants and animals share many abilities, the extent (33) which plants can exercise some of those abilities is (34) . For example, both plants and animals need food, water, and warmth for growth, (35) plants can move to (36) those needs only by the slow extraction of their leaves and roots, while animals can move relatively (37) distances in relatively little time. When an animal is hurt with needle, the animal will (38) the part of the body (39) . This ability to draw back (40) pain or irritation, called irritability, is found only to a very limited extent in plants.
If plants (41) the same (42) as animals, animals would have had a more difficult time finding food. If animals were as limited as plants, they might (43) a means of manufacturing their own food, as plants do now. The world would be a very different place (44) it is if the characteristics of plants and animals were (45)

A．livable

B．alive

C．living

D．lively
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单项选择题

现行的《城市区域环境振动标准》(GB 10070—88)规定了城市各类区域铅垂向Z振级标准值及其适用地带范围。其中，居民、文教区的昼间铅垂向Z振级标准值是( )。

A．67dB
B．70dB
C．72dB
D．75dB
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