（） is to get the materials and services from a company.

[单选题]Which of the following materials is a good insulator?( )A．SteelB．AluminumC．GlassD．Copper

[试题]The new music was built out of materials already in______. (exist)：blues，rock'n'roll，folk music.

[单选题]The chefs in thisrestaurant [insist on] high standards of materials.A.depen

[单选题]In the（ ），businesses offer services for which they charge a fee that is based on the number of size of transactions they process.Some of these services lend thenselves well to operating on the Web.A．Fee-for-Transaction Revenue ModelB．Advertising-Supp

[单选题](14)A．) getB．) get-nextC．) setD．) trap

[单选题]The high-speed data services for the interconnection of computer networks are usually referred to as ______ connections．A．LANsB．MANsC．WANsD．ATM

[单选题]When selecting listening materials，a text spoken at_________is preferred．A.

[判断题] 网络管理协议的一个关键功能Get是通过Get-Request、Get-Response和Get-Next-Request3种消息来实现的。A . 正确B . 错误

[单选题]D．eploying enhanced broadband services over existing network infrastructure （ ）in increase of the network complexity and therefore,extra expenses on network management and maintenancA．[1分]B．resultsC．resultedD．resultingE．result

[单选题]The network layer provides services to the transport layer．It call be based on either virtual circuits or datagrams．In both cases，its main job is（ ）packets from the source to the destination． A．dealing with B．sending C．routing D．receiving