题目内容

设有关系R(A,B,C)，在下列的等式中，不成立的是

A. σA＜2(πA，B(R))=π A,B(σA＜2(R)
B. πA,C(σA＜2(R) =σA＜2(πA,C(R))
C. πB,C(σA＜2(R) =σA＜2(πB,C(R))
D. πA(ЛA,B(R))=π A(R)

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Task 2
Directions: This task is the same as Task 1. The 5 questions or unfinished statements are numbered 41 through 45.
The traditional view of the Chinese family was that of a large extended family, with several generations and immediate families all living under One roof, being a self-sufficient and self-help organization for its members, providing child care and the care of the elderly. This is no longer true for the modern Chinese family. The Chinese family structure is mainly a nuclear one with husband and wife living with their children and sometimes their parents.
For the Chinese, the roles of mother and father are still quite clearly defined and separated. The Chinese saying "The man is responsible for the external and the woman the internal" is still true for many Chinese. It means that the man's job is to work to earn money for the family while the woman% job is to take care of the household so that the man can enjoy a comfortable and trouble-free family life. Even though many Chinese women now work outside the home, they are still mainly responsible for the care and upbringing of children.
Chinese parents in general are concerned about the discipline of their children with an emphasis on proper and appropriate behavior. Their role in their children's discipline is best described by "A kind mother and a strict father", which has been traditionally regarded as the Chinese parents' role in creating an ideal environment for disciplining children. Chinese mothers are usually the main caring people for their children by teaching them how to behave and helping them to distinguish what is right or wrong. Chinese fathers are seen by their children as a strict disciplinary figure and they have the authority to execute punishment, including corporal punishment when necessary. As a result, the children usually treat their father with respect but try to keep a distance from him.
It can be inferred from the passage that in a traditional Chinese family ______ are taken care of.

A. both children and the elderly
B. family resources
C. servants
D. women

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下图所示为一棵二叉排序树，其存储采取llink-rlink法。现要删除指针q所指的结点，不能得到正确结果的操作序列是

A. q^．info：=q^．llink^．info； q^．llink：=nil：
B. q^．info：=q^．rlink^．llink^．info； q^．rlink^．llink：=nil；
C. p^？llink：=q^？llink； p^．llink^．rlink：=q^．fiink；
D. p^．llink：=q^．rllink； p^．llink^．flink：=q^．llink：

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在评估销售成本率较低的服务类企业的价值时，通常优先考虑使用市净率模型。

A. 正确
B. 错误

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资本市场有效原则是指在资本市场上频繁交易的金融资产的市场价值反映了所有可获得的信息，而且面对新信息完全能迅速地做出调整。()

A. 正确
B. 错误

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设有关系R(A,B,C)，在下列的等式中，不成立的是

A. σA＜2(πA，B(R))=π A,B(σA＜2(R) B. πA,C(σA＜2(R) =σA＜2(πA,C(R)) C. πB,C(σA＜2(R) =σA＜2(πB,C(R)) D. πA(ЛA,B(R))=π A(R)

下图所示为一棵二叉排序树，其存储采取llink-rlink法。现要删除指针q所指的结点，不能得到正确结果的操作序列是

在评估销售成本率较低的服务类企业的价值时，通常优先考虑使用市净率模型。

资本市场有效原则是指在资本市场上频繁交易的金融资产的市场价值反映了所有可获得的信息，而且面对新信息完全能迅速地做出调整。()

A. σA＜2(πA，B(R))=π A,B(σA＜2(R)
B. πA,C(σA＜2(R) =σA＜2(πA,C(R))
C. πB,C(σA＜2(R) =σA＜2(πB,C(R))
D. πA(ЛA,B(R))=π A(R)