多项选择题
Which two states are the port states when RSTP has converged?（）
A.blocking B.learning C.disabled D.forwarding E.listening
多项选择题 Which two are advantages of static routing when compared to dynamic routing?（）
多项选择题 Why do large OSPF networks use a hierarchical design?（）
多项选择题 What are three features of the IPV6 protocol?（）
