保持阀的功用是使降压风缸内的压力一般控制在（）。 ["340～360kPa","280～340kPa","420～450kPa","340～420kPa"]
A UNIX user named Bob wants to replace his chess program with a new one， but he is not sure where theold one is installed. Bob is currently able to run a Java chess program starting from his home directory /home/bob using thecommand： java -classpath /test：/home/bob/downloads/*.jar games. Chess Bob’s CLASSPATH is set （at login time） to： /usr/lib：/home/bob/classes：/opt/java/lib：/opt/java/lib/*.jar What is a possible location for the Chess.class file？（） ["\/test\/Chess.class","\/home\/bob\/Chess.class","\/test\/games\/Chess.class","\/usr\/lib\/games\/Chess.class","\/home\/bob\/games\/Chess.cla"]
贯彻以预防为主，努力消除导致公路损毁的因素，增强设施的耐久性，提高抗御自然灾害的能力是公路养护的基本方针之一。
You are provisioning a DS-1 circuit on an ONS 15454 UPSR configuration and XC-10G card. How many total VT ports are used within the VT matrix at the source node?（） ["0","1","2","3","4"]
具有通气、增温、保墒、促进根系发育作用的田间管理措施是（）。 ["蹲苗","搭架","中耕","打杈"]
试说明在浏览器中显示XML文档的主要技术有哪些？
