F．or any information system to serve its purpose,the information must be ( ) when it is needed.

A．integral

B．available

C．irreplaceable

D．confidential

[单选题]For any information system to serve its purpose，the information must be( )w

[单选题]The most [urgent]problem any economic system faces is how to use its scarce

[单选题]The most [crucial]problem any economic system faces is how to use its scarc

[单选题]The most [crucial]problem any economic system faces is how to use its scarc

[单选题]means“Any HTML document on an HTTP Server”．A．Web ServerB．WebpageC．Web BrowserD．Website

[单选题]To search for any information needed on tomorrow’s Web, one only has to _____.［A］wade through screen after screen of extraneous data［B］ask the Web to dispatch some messenger to his door［C］use smart software programs called “agents”［D］explore Web site

[单选题]There is （） in any water cooling system for a diesel engine allowing for expansion and water make-up in the system as well as air vent and chemicals addition.A . a setting tankB . a service tankC . a head tankD . an expansion joint

[单选题]Information,in its most restricted technical sense,is a seque of symbols that can be interpreted as a message.ingormation can be recorded as signs,or transmitted as（）A .symbolsB .messageC .signalsD .wave

[填空题] FICS（File&Information converting System）工具主要是对（）的原始测试数据进行分析的工具。

[名词解释] 英译中：Geographic information system