[阅读理解]

【题干】网络可以通过不同的设备互连。 在物理层， 网络用中继器(reapers) 或集线器互连， 它们只是在相同的网络之间传送比特串。 在比物理层高一层的数据链路层，可以使用网桥和交换机， 它们能够接收数据帧(frames) ， 检测 MAC 地址， 并可以实现少量的协议转换， 把数据帧转发到不同的网络中。 在网络层， 我们可以使用路由器连接两个网络。 如果两个网络有着不同的 (dissimilar) 网络层， 路由器能够对分组格式进行转换。 在传输层， 我们使用传输网关， 它可以在两个传输连接之间建立接口。 最后， 在应用层， 应用网关实现消息语法(syntax) 之间的翻译。例如， 在 Internet 邮件和 X. 400 邮件之间的网关必须对邮件报文进行语法分析(parse) ， 并对报文各个字段做出修改。
The purpose of the requirements definition phase is to produce a clear,
complete, consistent, and testable(36)of the technical requirements for the software product.
During the requirements definition phase, the requirements definition team uses an interative process to expand a broad statement of the system requirements into a complete and detailed specification of each function that the software must perform and each (37) that it must meet. The starting point is usually a set of high level requirements from the (38) that describe the project or problem.
In either case, the requirements definition team formulates an overall concept for ' the system and then defines (39) showing how the system will be operated, publishes the system and operations concept document and conducts a system concept review (SCR) .
Following the SCR, the team derives (40) requirements for the system from the high level requirements and the system and operations concept using structured or object-oriented analysis. The team specifies the software functions and algorithms needed to satisfy each detailed requirement.

【题目】39.A. roles
B. principles
C. scenarios
D. scenes

1、[单选题]Their company used international lawyers to prosecute a crime ring involving software＿＿＿＿＿＿＿＿in Thailand.

• A、cloning
• B、piracy
• C、copying
• D、duplication

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2、[多选题]Instruction format in RISC has

• A、many kinds
• B、one or a few kinds
• C、one kind
• D、a few kinds

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3、[多选题]Viruses all have two phases to their eｘecution,the()and the().

• A、creaｔe phase
• B、del()ete phase
• C、infection phase
• D、attack phase

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4、[多选题]In order to increase our computer’s performance we need to

• A、have a much larger main memory
• B、have a L2 cache
• C、buy a L2 cache
• D、buy a L1 cache

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5、[多选题]The two most common types of scanners are()and()

• A、hand-held scanners
• B、handler scanners
• C、flatbed scanners
• D、auto scanners

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