In the IS-IS network as shown in the figure, RTA, RTC, RTD, and RTE establish a Level-2 neighbor relationship with each other; RTB, RTA, and RTC establish a Level-1 neighbor relationship. After the reasons for each router are stable, when RTB accesses 192.168.14.1, the next hop is ______.
If RTC adds the following configuration at this time:
RTC-isis-1]import-route isis level-2 into level-1
Then when RTB accesses 192.168.4.1, the next hop is ______.

Two MSR routers, MSR-1 and MSR-2, are interconnected on the 172.16.16.0/20 network segment. Now it is necessary to configure OSPF protocol on router MSR-1 to establish an adjacency relationship with MSR-2. Which of the following configurations is infeasible? (Select one or more) (Select one or more)

In the IS-IS network shown in the figure, each router is configured as follows.
RTA-isis-1]cost-ste compatible
RTB-isis-1] cost-ste wide-compatible
RTC-isis-1]cost-ste narrow-compatible
Then it is _______ that can correctly calculate the link cost between each other.

In the topology shown in the figure, the following configurations are performed on RTA, RTB, RTC and RTD respectively:
RTA-LoopBack0] ip address 1.1.1.1 255.255.255.255
RTA]ospf 1
RTA-ospf-1]area 1
RTA-ospf-1-area-0.0.0.1]network 10.0.0.0 0.0.0.255
RTA-ospf-1]import-route direct
RTB-LoopBack0] ip address 2.2.2.2 255.255.255.255
RTB]ospf 1
RTB-ospf-1]area 1
rtb-ospf-1-area-0.0.0.1]network 10.0.0.0 0.0.0.255
RTB-ospf-1-area-0.0.0.1]area 0
rtb-ospf-1-area-0.0.0.0]network 2.2.2.2 0.0.0.0
RTB-ospf-1-area-0.0.0.0]network 20.0.0.0 0.0.0.255
RTC-LoopBack0] ip address 3.3.3.3 255.255.255.255
rtc]ospf 1
RTC-ospf-1]area 0
RTC-ospf-1-area-0.0.0.0]network 20.0.0.0 0.0.0.255
rtc-ospf-1-area-0.0.0.0]area 2
RTC-ospf-1-area-0.0.0.2]nssa default-route-advertise
rtc-ospf-1-area-0.0.0.2]network 30.0.0.0 0.0.0.255
rtc-ospf-1-area-0.0.0.2]network 3.3.3.3 0.0.0.0
RTD-LoopBack0] ip address 4.4.4.4 255.255.255.25
RTD]ospf 1
RTD-ospf-1]area 2
RTD-ospf-1-area-0.0.0.2]network 30.0.0.0 0.0.0.255
rtd-ospf-1-area-0.0.0.2]nssa
RTD-ospf-1]import-route direct
Which of the following routes may exist in the RTD's routing table _______.

Regarding the stub area and NSSA area of ​​the OSPF protocol, the following statements are incorrect: _______