As shown in the network below, all switches enable STP protocol. Disable SWA's G0/0/2 port configuration BPDU sending function, SWC G0/0/1 re-converges to become the root port, about this process, which of the following statements are correct? (Multiple Choice)

When the IPv4 protocol is used as the network layer protocol, which field is not included in the network layer header?

If the network address of a network is 10.1.1.0/30, what is its broadcast address?

Apply the ACL configured as shown in the figure in Telnet. Only the device with the IP address of 172.16.105.2 is allowed to log in remotely:
#
acl number 2000
rule 5 permit source 172.16.105.2 0
#

The information shown in the figure is the port status information displayed on a switch running STP. According to this information, what is wrong in the following description? () (Single-choice question)