[单选] 铁路危险货物包装根据其内装的危险程度划分为三种包装类别：Ⅰ类包装--具有（）危险性。

站、车广播要坚持计划性、针对性、思想性和（）相统一的原则。 艺术性。 知识性。 趣味性。 科学性。 经济增长 Refer to the exhibit. Which rule does the DHCP server use when there is an IP address conflict?（） The address is removed from the pool until the conflict is resolved.。 The address remains in the pool until the conflict is resolved.。 Only the IP detected by Gratuitous ARP is removed from the pool.。 Only the IP detected by Ping is removed from the pool.。 The IP will be shown, even after the conflict is resolved.。 操行评定的原则是什么？ 旁通管的管径应根据最低进口压力和最大出口流量确定，一般最小管径不小于DN（）mm。 50。 80。 100。 120。 铁路危险货物包装根据其内装的危险程度划分为三种包装类别：Ⅰ类包装--具有（）危险性。