火灾的种类按燃烧物的性质划分,以下不属于可燃金属的物质是()。 ["钾","钠","镁","铜"]
动火操作人员必须办理()才可动火操作 ["动火许可证","操作证","工作证","领导批示"]
下面哪种不是旋转工具()。 ["砂轮机","锉刀","钻床","电钻"]
在OSPF协议中,当接口网络类型为NBMA(非广播多路访问)时,其默认Hello时间间隔和邻居失效时间分别为() ["10,30","10,40","30120","40120"]
备用电源系统的故障由什么监控() ["BPC","UB.SPCU","GCU","LRU"]
标定KMnO4标准溶液的浓度时,精密称取0.3562g基准草酸钠溶解并稀释至250mL容量瓶中,精密量取10.00mL,用该标准溶液滴定至终点,消耗48.36mL,计算KMnO4标准溶液的浓度。