某工作站无法访问域名为www.test.com 的服务器，使用ping 命令对该服务器的IP地址进行测试，响应正常；但是对服务器域名进行测试时出现超时错误。可能出现的问题是 （55） 。

（55）

A query is used to search through the database to locate a particular record or records,which conform. to specified （75） .

（75）

Firewall is a （74） mechanism used by organizations to protect their LANs from the Internet.

（74）

A Web （73） is one of many software applications that function as the interfacebetween a user and the Internet.

（73）

（72） is the conscious effort to make all jobs similar, routine, and interchangeable.

（72）

An （70） statement can perform. a calculation and store the result in a variable sothat it can be used later.

（70）

Each program module is compiled separately and the resulting （71） files are linkedtogether to make an executable application.

（71）

In C language, （69） are used to create variables and are grouped at the top of aprogram block.

（69）

（68） are those programs that help find the information you are trying to locate onthe WWW.

（68）

In C language, a （67） is a series of characters enclosed in double quotes.

（67）