给水管配水出口与用水设备溢流水位的最小间隙为给水管径的（）倍。 ["4.0","3.0","2.5","1.5"]
按GB7588-2003《电梯制造与安装安全规范》规定，曳引轮的节圆直径与悬挂绳的公称直径之比应不小于（）。 ["30","40","50"]
Which of the following local files is used to run the date command on the remote machine "Earth" using the following rexec command without request for a password？ rexec Earth date（）。 ["~\/ .rhosts","$HOME\/.netrc","\/etc\/hosts.equiv","\/etc\/security\/user"]
家庭联产承包责任制
除锈的目的在于获得（） ["光洁的表面","好的附着力","材料精度","材料形状"]
生物性污染
