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- A． 255．240．0．0
- B．255．255．0．0
- C．255．255．252．0
- D．255．255．255．252
- 5
-
●R
- avi, like many project&n
- bsp; (71) ,had studied the waterfall model of software development as the primary software life-
- cycle (72) ．He was all set to use it for an upcoming project, his first assignment． However, Ravi foun
- d that the waterfall model could not be used because the customer wanted the software delivered in stages, something that implied that the system had to be delivered and built in (73) and not as (74) ．The situation in many other projec
- choice． To be the most suitable, an existing process must be (75) to the new problem．Adevelopment process, even after tailoring, generally cannot handle change requests． Toaccommodate change requests without losing control of the project, you mu
- A．电信网、广播电视网、互联网
- B．物联网、广播电视网、电信网
- C．物联网、广播电视网、互联网
- D．物联网、电信网、互联网
- A．物理层
- B．数据链路层
- C．网络层
- D．传输层 (67)
- A．实现MAC地址与主机名之间的映射
- B．实现IP地址与MAC地址之间的变换
- C．实现IP地址与端口号之间的映射
- D．实现应用进程与物理地址之间的变换
- A．交换机是一种多端口网桥
- B．交换机的各个端口形成一个广播域
- C．集线器的所有端口组成一个冲突域
- D．集线器可以起到自动寻址的作用
- A．数据仓库服务器
- B．OLAP服务器
- C．查询和报表工具
- D．数据挖掘工具
- A．关联规则
- B．特征描述
- C．分类
- D．聚类
- A．将实体的码分别和每个多值属性独立构成一个关系模式
- B．将多值属性和其它属性一起构成该实体对应的关系模式
- C．多值属性不在关系中出现
- D．所有多值属性组成一个关系模式 (61)
- A．2NF
- B．3NF
- C．BCNF
- D．4NF
- address varchar(50))；
- CREATE TYPE Student( under Person (degree char(20)
- department char(20)）； (62)
- A．类型继承
- B．类型引用
- C．表继承
- D．无任何关系
- A．数据流图
- B．类图
- C．E-R图
- D．用例图
