简述架空线路的构成与优缺点？

对于220kV及以下系统，系统绝缘水平一般可以承受操作过电压冲击，但超高压系统的操作过电压较高，设计时要作（）。

《孙子兵法》云：“投入亡地然后存，陷入死地而后生。”韩信据此，背水一战,大破赵军；马谡据此，屯兵山上，痛失街亭。这两个事实说明

A．意识对物质具有反作用

B．物质决定意识，而不是意识决定物质

C．意识具有相对独立性

D．主观和客观的统一是具体的历史的统一

设有定义"chara=2，b=5；"求表达式"～a^b＜＜2"的值(假定现有计算机字长为16) ( )

A．-32

B．32

C．-23

D．23

同步注浆的浆液稠度须控制在（）范围内。

A.10～11cm 

B.10.5～11.5cm 

C.11.5～12.5cm

Passage Three

The age at which young children begin to make moral discriminations about harmful actions committed against themselves or others has been the focus of recent research into the moral development of children. Until recently, child psychologists supported pioneer developmentalist Jean Piaget in his hypothesis that because of their immaturity, children under age seven do not take into account the intentions of a person committing accidental or deliberate harm, but rather simply assign punishment for transgressions on the basis of the magnitude of the negative consequences causeD. According to Piaget, children under age seven occupy the first stage of moral development, which is characterized by moral absolutism (rules made by authorities must be obeyed) and imminent justice (if rules are broken, punishment will be meted out). Until young children mature, their moral judgments are based entirely on the effect rather than the cause of a transgression. However, in recent research, Keasey found that six-year-old children not only distinguish between accidental and intentional harm, but also judge intentional harm as naughtier, regardless of the amount of damage produced. Both of these findings seem to indicate that children, at an earlier age than Piaget claimed, advance into the second stage of moral development, moral autonomy, in which they accept social rules but view them as more arbitrary than do children in the first stage.

Keasey’s research raises two key questions for developmental psychologists about children under age seven: do they recognize justifications for harmful actions, and do they make distinctions between harmfulacts that are preventable and those acts that have unforeseen harmful consequences Studies indicate that justifications excusing harmful actions might include public duty, serf-defense, and provocation. For example, Nesdale and Rule concluded that children were capable of considering whether or not an aggressor’s action was justified by public duty: five year olds reacted very differently to "Bonnie wrecks Arm’s pretend house" depending on whether Bonnie did it "so somebody won’t fall over it" or because Bonnie wanted "to make Ann feel bad". Thus, a child of five begins to understand that certain harmful actions, though intentional, can be justified; the constraints of moral absolutism no longer solely guide their judgments.

Psychologists have determined that during kindergarten children learn to make subtle distinctions involving harm. Darley observed that among acts involving unintentional harm, six-year-old children just entering kindergarten could not differentiate between foreseeable, and thus preventable, harm and unforeseeable harm for which the perpetrator cannot be blamed. Seven months later, however, Darley found that these same children could make both distinctions, thus demonstrating that they had become morally autonomous.

According to the passage, Darley found that after seven months of kindergarten six year olds acquired which of the following abilities ？（）

A．Differentiating between foreseeable and unforeseeable harm

B．Identifying with the perpetrator of a harmful action

C．Justifying harmful actions that result from provocation

D．Evaluating the magnitude of negative consequences resulting from the breaking of rules