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问题 填空题
设M是双曲线
x2
25
-
y2
9
=1的右支上的一点，F1为左焦点，且|MF1|=18，N是线段MF1的中点，O为坐标原点，则|ON|=______．
答案

由于M是双曲线

x2
25
-
y2
9
=1的右支上的一点，F1为左焦点，且|MF1|=18

所以|MF2|=18-2a=18-10=8

∵N是线段MF1的中点，O为坐标原点，

∴|ON|=

1
2
|MF2|=4

故答案为：4

单项选择题

下列关于全面指定交易制度说法不正确的是()

A.1998年4月1日起，上海证券交易所开始实行全面制定交易制度

B.在上交所交易市场从事证券交易的投资者，可以指定多家机构为其买卖证券的交易点

C.投资者与所选的证券营业部门签订“指定交易协议书”

D.办理相应的登记和结算手续后，该营业部应为其提供委托、交易、结算、查询及自动领取股票现金红利、按季或按月对账、办理配股等服务
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问答题

Children in any society are expected to learn to conform to a number of social rules and expectations if they are to become participants in the culture. (46)Among the rules that children in our society are expected to learn are that certain classes of adults (such as teachers and doctors) are addressed by titles, that males and females use separate restroom facilities, and that women but not men wear dresses. These are examples of social conventions. In the absence of such a shared norm, the acts are neither right nor wrong. For this reason, conventions may be said to be arbitrary. For example, (47)we could just as easily have students address teachers by first names as have them call teachers by their last names and formal titles of Mr. or Ms.
Conventions, however, serve an important function by providing predictability and order to social life. (48)Without social conventions it would be impossible to organize social institutions such as schools, and societies as organized systems could not exist. The arbitrariness of conventions makes their importance difficult for children to figure out. (49) It is not until some time in adolescence that children come to fully understand the function that these arbitrary conventions serve to provide predictability and order to our social interactions.
In contrast with issues of convention are matters of morality. Morality refers to issues of human welfare, justice, and rights that are a function of the inherent features of interpersonal relations. Because of this, the right and wrong of moral actions are not simply determined by social consensus or the views of authority. For example, it is not possible to hit another person with force and not hurt the other person. Similarly, it is not possible to steal something valuable from someone else and not cause the person to experience the sense of loss. A moral judgment about unprovoked harm ( "It is wrong to hit") would not be dependent on the existence of a socially agreed upon rule or standard but could be generated solely from the intrinsic effects of the act (i.e., hitting hurts). (50)Similar analyses could be done regarding a broader range of issues that would extend beyond direct harm to concerns for what it means to be just, compassionate, and considerate of the rights of others.
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