1. [单选题]下列哪个network命令会告知此路由器开始使用IP地址为10.1.1.1、10.1.100.1和10.1.120.1的接口上的OSPF（）
A. network 10.0.0.0 255.0.0.0 area 0
B. network 10.0.0.0 0.255.255.255 area 0
C. network 10.0.0.1 0.0.0.255 area 0
D. network 10.0.0.1 0.0.255.255 area 0
2. [多选题]Regarding the extended ping command; which of the statements below are true?(Select all valid answer choices)
A. The extended ping command is supported from user EXEC mode.
B. The extended ping command is available from privileged EXEC mode.
C. With the extended ping command you can specify the TCP and UDP port to be pinged.
D. With the extended ping command you can specify the timeout value.
E. With the extended ping command you can specify the datagram size.
3. [多选题]Why is full-duplex Ethernet superior to its single-duplex counterpart? (Select two answer choices.)
A. It uses inexpensive hubs
B. It operates without collisions
C. It operates on switches
D. It provides faster data transfer
E. It utilizes fewer wiring pairs
4. [单选题]交换机上VLAN的功能描述中，正确的是（）
A. 可以减少广播域的个数
B. 可以减少广播对网络性能的影响
C. 可以减少冲突域的个数
D. 可以减小冲突域的容量
5. [单选题]The 201.145.32.0 network is subnetted using a /26 mask. How many networks and IP hosts per network exists using this subnet mask?
A. 4 networks and 64 hosts
B. 64 networks and 4 hosts
C. 4 networks and 62 hosts
D. 62 networks and 2 hosts
E. 6 network and 30 hosts
