As shown in the figure below, all switches enable the STP protocol and keep other configurations in their default state. When the network is stable, which of the following statements are correct? (Multiple Choice)

All ports on the root bridge switch are designated ports.

A certain ACL of the router is in the following rules, rule deny source 192.168.2.0 0.0.0.255 destination 172.16.10.2 0.0.0.0 Which statement is correct?

If the broadcast address of a network is 172.16.1.255, what might its network address be?

Which of the following levels is not a common network level in mid-sized campus network architecture?