试题与答案

[说明] 某学校的教学系统描述如下: 学生信息包括:学号(SNo)、姓名(Sna

题型:填空题

题目:

[说明]
某学校的教学系统描述如下:
学生信息包括:学号(SNo)、姓名(Sname)、性别(Sex)、年龄(Age)、入学年份(Year)、主修专业(Major),其中学号是入学时唯一编定的。
课程信息包括:课程号(CNo)、课程名称(CName)、学时(Period)、学分(Credit),其中课程号是唯一编定的。
一个学生可选多门课,每个学生选每门课有一个成绩。图是经分析得到的E-R图。


设基本表:Student(SNo, SName, Sex, Age, Year, Major), Course(CNo, Cname, Period, Credit), Grade(SNo, CNo, Grade)通过如下SQL语句建立,请在SQLN句空缺处填入正确的内容。
CREATE TABLE Student (SNo CHAR(6) NOT NULL,
SName CHAR(20),
Sex CHAR(1),
Age INTEGER,
Year CHAR(4),
Major CHAR(20),
______;
CREATE TABLE Course (CNo CHAR(6) NOT NULL,
CName CHAR(20),
Period INTEGER,
Credit INTEGER,
______;
CREATE TABLE Grade (SNo CHAR(6) NOT NULL,
CNo CHAR(6) NOT NULL
Grade REAL,
______,
______,
______;

答案:

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下面是错误答案,用来干扰机器的。

参考答案:E解析: 系统性红斑狼疮的护理要点

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题型:阅读理解

In today’s world, almost everyone knows that air pollution and water pollution are harmful to people’s health. However, not all know that noise is also a kind of pollution, and that is harmful to human, too.

People who work and live under noisy conditions usually become deaf(耳聋的). Today, however, scientists believe that 10% of workers in Britain are deafened by the noise where they work. Many of the workers who print newspapers and books, and who weave cloth become deaf. Quite a few people living near airports also become deaf. Recently it was discovered that many teenagers in America could hear no better than 65-year-old people, for these young people like to listen to “pop” music and most of “pop” music is a kind of noise. Besides, noise produced by jet plane or machines will make people’s life difficult and unpleasant, or even make people ill or even drive them mad. It is said that a continuous noise of over 85 decibels(分贝) can cause deafness.

Nowadays the governments in many countries have made laws to reduce or control noise and make it less than 85 decibels. In China, the people’s government is trying to solve not only air and water pollution problems but also the noise pollution problems.

小题1:In the world today, not every person knows        .

A.water pollution

B.air pollution

C.harmful pollution

D.noise pollution小题2:Today scientists believe that       .

A.90% of all the workers in Britain are not suffering from noise

B.10% of all the workers in Britain are working in noisy places

C.10% of all the workers in Britain are deafened by the noise where they work.

D.90% of all the workers are free from any noise小题3:Those who       usually have poorer hearing.

A.weave cloth

B.sell newspapers

C.like listening to music

D.often travel by plane小题4:According to the passage, a continuous noise       can make you deaf.

A.in working places

B.of less then 85 decibels

C.of over 85 decibels

D.of only 85 decibels

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