皮皮学，免费搜题
登录
搜题
【单选题】
8-9:给定关系R(A, B,C,D)和S(C,D,E),若关系R与S进行自然连接运算,则运算后的元组属性列数为( 8 );关系代数表达式 与( 9 )等价。A.
4
B.
5
C.
6
D.
7
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
反馈参考答案：
举一反三
【单选题】Problems relating to people's livelihood have been the focus of the government, especially ______-Premier Wen Jiabao included them in his government work report last year. [ ]
A.
when
B.
as
C.
until
D.
since
【单选题】The government of PR China ______ that the above-mentioned ship complies with the provisions of the regulations annexed to the Convention referred to above as regards radiotelegraphy and radar．
A.
certifies
B.
confirms
C.
contains
D.
construes
【简答题】计算任意个整数之和,如1、3、5之和,1、3、5、7之和,以及1、3、5、7、9之和并输出到console控制台中。请把代码编写下来
【单选题】The world known characters of comic strip, Charlie Brown and Snoopy, were created by artist Charles Schulz who was born in Minnesota.
A.
Y
B.
N
C.
NG
【单选题】According to the last paragraph, 'self-fulfilling' is to 'self-avoiding' as ______.
A.
artistic to 'functional'.
B.
material to 'imaginary'.
C.
desirable to 'undesirable'.
D.
rational to 'emotional'.
【单选题】Problems relating to people's livelihood have been the focus of the government, especially _______ Premier Wen Jiabao included them in his government work report last year. [ ]
A.
when
B.
if
C.
until
D.
since
【简答题】阅读理解 Throughout the history of the arts, the nature of creativity has remained constant to artists.No matter what objects they select, artists are to bring forth new forces and forms that cause change...
【单选题】What sort of painter was Rembrandt at the beginning of his career?
A.
A poor, starving artist.
B.
A modern, radical artist.
C.
A famous, fashionable artist.
D.
A royal painter.
【简答题】定义一个复数类 Complex ,重载运算符“ + ”,使之能用于复数的加法运算。参加运算的两个运算量可以都是类对象,也可以其中有一个是整数,顺序任意。例如: c1+c2,i+c1,c1+i 均合法 ( 设 i 为整数 ,c1,c2 为复数 ) 。编程序,分别求两个复数之和、整数和复数之和。 已知两个复数:c1为(3+4i),c2为(5,-10i) 整数为 5 输出: c1+c2=(8,-6i) ...
相关题目：
参考解析：
知识点：
题目纠错 0
发布
