图示桁架在P作用下的内力如图示，EA=常数，此时C点的水平位移为：

A:0 B:(2．914Pa／EA)(→) C:(Pa／2EA)(→) D:(2．914Pa／EA)(←)

图示结构，EA=常数，C,D两点的水平相对线位移为：

A:2Pa／EA B:Pa／EA C:3Pa／2EA D:Pa／3EA

图示为超静定桁架的基本结构及多余未知力=1作用下的各杆内力，EA为常数，则δ为( )。

A:d(1.5+1.414)/EA B:d(2.5+1.414)/EA C:d(0.5+1.414)/EA D:d(1.5+2.828)/EA

图示结构，EA=常数，C、D两点的水平相对线位移为：（）

A:2Pa／EA B:Pa／EA C:3Pa／2EA D:Pa／3EA

若正反应的活化能Ea1大于逆反应的活化能Ea2，则正反应的热效应ΔH为（）。

A:ΔH＞0 B:ΔH＜0 C:ΔH＝（Ea1-Ea2）／2 D:不能确定

三相交流电源各电动势eA、、eB、eC之间，有（）的关系。

A:eC=eA－eB B:eA+eB+eC=0 C:eA+eB+eC=0 D:eA=eB+eC

图14-66（a）桁架，力法基本方程如图14-66（b），力法典型方程中的系数δ11为（）。

A:3.414ι/EA B:-4.828ι/EA C:4.828ι/EA 2.0ι/EA

The pursuit of information has been a human preoccupation since knowledge was first recorded. In the 3rd century BC Ptolemy stole every (1) scroll from passing travellers to (2) his great library in Alexandria. After 2001 America (3) a program to compile as many data as possible about just about everything. Since 1996 Brewster Kahle has been (4) all the content on the web as a not-for-profit (5) called the "Internet Archive". It has (6) expanded to software, films, audio recordings and scanning books.
There has always been more information than people can mentally process. The disparity between the amount of information and man’s ability to deal with it may be (7) , but that need not be a cause for (8) Our sensory and attentional systems are tuned to be (9) People find patterns to compress information and make it manageable. (10) Commander Schmorrow does not think that man will be (11) by robots. "The flexibility of the human to consider as-yet-unforeseen (12) during critical decision-making, go (13) the gut when problem-solving under uncertainty and other such (14) reasoning behaviours will not be readily replaced by a computer," he says.
The (15) of data now available is a resource, similar to other resources and even to technology itself. (16) , resources and technologies are neither good nor bad; it depends on how they are (17) . In the age of big data, computers will be monitoring more things, making more decisions and even (18) improving their own processes--and man will be left with the same (19) he has always faced. (20) T.S. Eliot asked: "Where is the wisdom we have lost in knowledge Where is the knowledge we have lost in information/

A:replaced B:integrated C:assisted D:supported

Throughout history man has had to accept the fact that all living things must die, but people now live longer than they (36) . Yet, all living things still show the (37) of aging, which will eventually. (38) death.
Aging is not a disease, but as a person passes maturity, the cells of the body and the (39) they form do not function as well as they (40) in childhood and adolescence (青春期). The body provides less (41) against disease and is more prone (42) accident.
A number of related cause may (43) aging. Some cells of the body have a fairly long life, but they are not (44) when they die. As a person ages, (45) of brain cells and muscle cells decrease, (46) body cells die and are replaced by new cells. In an aging person the (47) cells may not be as viable (能生存的) or as capable (48) growth as those of a young person.
Another (49) in aging may be changes within the cells (50) . Some of the protein chemicals in cells are known (51) with age and become less elastic. This is why the skin of old people wrinkles and (52) . This is also the reason old people (53) in height. There may be other more important chemical changes in the cells. Some complex cell chemicals, such as RNA, store and (54) information that the cell need. Aging may affect this (55) and change the information carrying molecules so that they do not transmit the information as well.

A:replaced B:reborn C:recovered D:yielded

Throughout history man has had to accept the fact that all living things must die, but people now live longer than they (36) . Yet, all living things still show the (37) of aging, which will eventually. (38) death.
Aging is not a disease, but as a person passes maturity, the cells of the body and the (39) they form do not function as well as they (40) in childhood and adolescence (青春期). The body provides less (41) against disease and is more prone (42) accident.
A number of related cause may (43) aging. Some cells of the body have a fairly long life, but they are not (44) when they die. As a person ages, (45) of brain cells and muscle cells decrease, (46) body cells die and are replaced by new cells. In an aging person the (47) cells may not be as viable (能生存的) or as capable (48) growth as those of a young person.
Another (49) in aging may be changes within the cells (50) . Some of the protein chemicals in cells are known (51) with age and become less elastic. This is why the skin of old people wrinkles and (52) . This is also the reason old people (53) in height. There may be other more important chemical changes in the cells. Some complex cell chemicals, such as RNA, store and (54) information that the cell need. Aging may affect this (55) and change the information carrying molecules so that they do not transmit the information as well.

A:replaced B:reborn C:recovered D:yielded