Which of the following is the maximum length of the Ethernet frame encapsulated by QinQ?

As shown in the figure, the asymmetric VLL FRR networking is used. AC
interfaces on PE 1, PE 2, and PE 3 are configured as follows:
Configuration of the AC interface on PE 1:
interface Pos3/0/1link-protocol ppp
undo shutdown
oam detect lcp-terminal notify lcp-terminal
ip address 208.1.1.1 255.255.255.0
ip address 208.2.2.1 255.255.255.0 sub
mpls l2vc pw-template pw1 13579 ip-interworking
mpls l2vc pw-template pw2 24680 ip-interworking secondary
mpls l2vpn oam-mapping
mpls l2vpn reroute immediately resume 0
Configuration of the AC interface on PE 2:
interface Pos1/0/3
link-protocol ppp
undo shutdown
ip address 208.1.1.2 255.255.255.0
mpls l2vc pw-template pw1 13579 ip-interworking
mpls l2vpn oam-mapping
Configuration of the AC interface on PE 3:
interface Pos1/0/0
link-protocol hdlc
undo shutdown
oam detect hello-stop notify hello-stop
ip address 208.2.2.2 255.255.255.0
mpls l2vc pw-template pw1 24680 ip-interworking
mpls l2vpn oam-mapping
Which of the following statements are true on the condition that IGP and MPLS are configured correctly on the public network?

Which statement about the MPLS LSP traceroute is true?

BGP often uses AS PATH to control inter-area routes. Which of the following regular expressions helps ensure that routes within AS 100 and neighboring ASs are received from only one EBGP neighbor?

Exhibit:

As shown in the figure, external route 1.1.1.0/24 is imported to RTA that is located in the NSSA area RTD is a backbone area router. RTB and RTC are both area border router (ABRs). OSPF configuration are as follows.

Which statement is true?