如果+20m表示物体向东运动20米,那么-20米表示( )。
物体向西运动20米
购买现成的软件开发工具还是自己开发专用的工具与具体工作的____________、环境、人员素质、项目特征都有不可分割的联系。
Traditional Internet access methods like dial-up were so slow that host computers were connected to the dial-up. (6) at the customer premise over slow (7) ports. PPP was designed to run directly over these serial links. But with the advent of broadband Internet (8) technologies such as ADSL and cable modems there has been a considerable increase in the bandwidth delivered to the end users. This means that the host computers at the customer premise connect to the (9) or cable "modem" over a much faster medium such as Ethernet. It also means that multiple (10) can connect to the Internet through the same connection.
(10)是()
A.cables
B.hosts
C.servers
D.modems