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一个不多于50台主机的网络，合适它的掩码是多少？

问答题一个不多于50台主机的网络，合适它的掩码是多少？

whatisadministrativedistance.

问答题what is administrative distance.

InmulticastnetworkhowtoselectDR？andwhatistheorder？

问答题In multicast network how to select DR？ and what is the order？