磁力线上任意一点的切线方向，就是该点的磁场方向，即小磁针在磁力作用下（）极所指的方向。 ["N极","S极","N极或S极","S极或N极"]
关于圆钢说法正确的有（） ["圆钢与圆钢搭接的长度应为其自身直径的10倍","要求上下搭接","焊接时要求双面焊接"]
空间数据分层的方法有（）三种类型。 ["按专题分层","按主题分层","按需求分层","以地面垂直高度分层","按时间序列分层"]
Client association using EAP-Cisco Wireless （LEAP） is failing， but EAP-PEAP is functioning on an autonomous access point. Which of the following needs to be enabled on the access point so EAP-Cisco Wireless （LEAP） is enabled？（） ["open authentication plus MAC","open authentication plus EAP","shared key","network EAP"]
地面的消防水池必须经常保持不少于m3的水量。（） ["200","150","100"]
气门叠开
