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问题 填空题

多项式5x2-7x-3是______次______项式．

答案

依题意得原式是二次三项式．

故填：二，三．

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．whether

B．and

C．both

D．all
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单项选择题 案例分析题

下图为地处北纬50附近欧洲中部的某聚落局部地区示意图。读图，回答下列问题。

该聚落（）

A.主要分布在河流西侧的阶地上

B.坐落在河流冲积平原上

C.自然景观以荒漠为主

D.居住区适宜向河滩扩展
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