文档介绍：reason is that it is written mostly in the C language instead ofa machine language for a specific system. Second, UNIX has a powerful set of utilities (commands) that can bined in an executable file called a script to solve many problems that require programming in other operating systems. Third, it is device independent because it includes the device drivers in the operating system itself, which means that it can be easily configured to run any device. In summary, UNIX has every feature that a powerful operating system has. The only criticism heard often about UNIX is that mands are short and esoteric (深奥的) for normal users; in fact, it is very convenient for programmers who need mands. UNIX 是一个在计算机程序设计员和计算机科学家中广为流行的操作系统。它是一个非常强大的操作系统, 具有三个显著的特点。第一, UNIX 是可移植的操作系统, 可以只经过少量改动而从一个平台移植到另一个平台。原因是它多半用 C 语言编写,而不是用于特定系统的机器语言。第二, UNIX 拥有一套功能强大的实用程序(命令) ,它们能够组合成被称为脚本的可执行文件, 去解决许多问题, 而这一工作在其他操作系统中则需要通过编程来完成。第三, 它具有设备无关性, 因为操作系统本身就包含了设备驱动程序, 这意味着它易于配置,去运行任何设备。概括地说, UNIX 具有一个强大的操作系统所拥有的一切特点。惟一经常听到的有关 UNIX 的批评是,它的命令短而且对一般用户来说很深奥。事实上,这一点对于需要短命令的程序设计员非常方便。 PAPER TW O P art One: Choose among the four choices the one that pletes the sentence. (10 points) ________ copy isa copy ofa current file made in order to protect against loss or damage. A. hard B. backup C. soft D. file 2. The infamous “ Michelangelo ”________ strikes thousands puters every year on March 6 th. A. cracker B. hacker C.