设有如下三个关系表

下列操作中正确的是( )。

单项选择题若进程P1正在运行，操作系统强行撤下P1进程所占用的CPU，让具有更高优先级的进程P2运行，这种调度方式称为(7)，此时P1进程处于(8)状态。(9)将CPU的时间分成若干个时间片轮流地为各个用户服务。

单项选择题数字用户线路接入种类很多，其中非对称数字用户线是(43)。光纤接入网有多种，其中(44)是最理想的。

单项选择题下列程序执行后的结果是______。 package ch1; import java.io.*; public class ex22 { static, String filename = 'ch1 kfile22.txt'; public static void main(String[] args) { try { FileWriter fr = new FileWriter(filename); PrintWriter pr = new PrintWriter(fr); String name = 'xiaoming'; String phone = '123456'; String age = '12'; pr.println(name + ',' + phone + ',' + age); pr.close(); fr.close(); } catch(IOException ioe) { ioe.printStackTrace() } } }

单项选择题以下选项中不采用组播协议的应用是(125)。在IPV4地址中，(126)类地址作为组播地址。

单项选择题下列复用方式中，(112)是光纤通信中使用的复用方式，EI载波把32个信道按(113)方式复用在一条2.048Mb s的高速信道上，每条话音信道的数据速率是(114)。

单项选择题(接上一题)该点与计划S曲线的水平距离表示(70)。

单项选择题Personal firewall is a technology that helps(66)intruders from accessing data on your PC via the Internet or another network, by keeping(67)data from entering or exiting your system.Hackers do not just target national security organizations for(68): They want your tax returns, network passwords, or bank account numbers. And you do not want the FBI kicking in your door because someone hijacked your PC to(69)in the latest denial-of-service attack on the Internet. Now that 'always-on' broadband connections such as cable modems and digital subscriber line are becoming more popular, home users are at risk. Fortunately, you can protect your data. Firewalls can block(70)attacks and protect your PC from outside threats.

单项选择题data effectively is crucial for success in today's competitive environment. Managers must know how to use a variety of tools. Integrated data takes information from different sources and puts it together in a meaningful and useful way. One of the difficulties of this is the(72)in hardware and software.(73)integration uses a base document that contains copies of other objects.(74)integration uses a base document that contains the current or most recent version of the source document it contains.(75)provides an overview of the program written in' plain' English, without the computer syntax.

单项选择题将十进制数-0.3125化成定点二进制补码表示的小数是(5)。将该数表示成二进制浮点规格化数，其阶码3位，尾数5位(均含1位符号)，都用补码表示，该浮点数是(6)。

单项选择题由6个字符的7位ASCII编码排列，再加上水平垂直奇偶校验位构成下列矩阵(最后一列为水平奇偶校验位，最后一行为垂直奇偶校验位)。字符：则X1X2X3X4处的比特分别为(7)；X5X6X7X8处的比特分别为(8)；X9X10X11X12处的比特分别为(9)。