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问题 选择题

在平直公路上做匀加速行驶的汽车，因漏油，每经过 T时间从离路面髙h处漏下一滴油，油滴在路面上形成一段 油点痕迹,如图所示。已知油点痕迹P是汽车运动到Q处 时滴下在路面形成的,现测出油痕迹P至其前后相邻两点 的距离分别为s1和s2,若汽车运动加速度大小为a,运动到 Q点时速度大小为v;则下列正确的是

A．

B．

C．

D．

答案

答案：B

题目分析：由匀变速直线运动规律：连续相邻相等时间的位移之差为常数知s2-s1=aT2；中间时刻的速度等于这段时间的平均速度V=，得B正确，

不定项选择

证券公司从事客户资产管理业务，应当按规定向中国证监会申请客户资产管理业务资格，经中国证监会批准，证券公司可以从事（）。

A．为客户办理特定目的专项资产管理业务

B．为多个客户办理集合资产管理业务

C．单一客户办理定向资产管理业务

D．单一客户办理非定向资产管理业务
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单项选择题

Attempts to understand the relationship between social behavior and health have their origin in history. Dubos (1969) suggested that primitive humans were closer to the animals (1) they, too, relied’upon their instincts to stay healthy. Yet some primitive humans (2) a cause and effect relationship between doing certain things and alleviating (3) of a disease or (4) the condition of a wound. (5) there was so much that primitive humans did not (6) the functioning of the body, magic became an integral component ofthe beliefs about the causes and cures of heath (7) Therefore it is not (8) that early humans thought that illness was caused (9) evil spirit. Primitive medicines made from vegetables or animals were invariably used in combination with some form of ritual to (10) harmful spirit from a diseased body.

One of the. earliest (11) in the Western world to formulate principles of health care based upon rational thought and (12) of supernatural phenomena is found in the work of the Greek physician Hippocrates. The writing (13) to him has provided a number of principles underiying modern medical practice. One of his most famous (14) , the Hippocratic Oath, is the foundation of contemporary medical ethics.

Hippocrates also argued that medical knowledge should be derived from a (15) of the natural science and the logic of cause and effect relationships. In this (16) thesis, On Air, Water, and Places, Hippocrates pointed out that human well-being is (17) by the totality of environmental (18) : living habits or lifestyle, climate, geography of the land, and the quality of air, and food. (19) enough, concerns about our health and the quality of air, water, and places are (20) very much written in twentieth century.

9（）

A.in

B.by

C.off

D.up
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