1. [多选题]With regard to Ethernet media access methods, which of the following are true?(Choose all that apply.)
A. A device waits for an electronic signal before transmitting.
B. A device listens and waits until the media is not busy before transmitting.
C. All devices on an Ethernet segment see data that passes on the network medium.
D. Only the sender and the receiver devices see data that passes on the network medium.
E. Ethernet networks allow you to configured devises with higher transmission priority.
2. [多选题]When you compare the differences between half-duplex and full-duplex Ethernet, which of the following characteristics are exclusive to half-duplex? (Select two answer choices)
A. Half-duplex Ethernet operates in a shared collision domain.
B. Half-duplex Ethernet operates in an exclusive broadcast domain.
C. Half-duplex Ethernet has efficient throughput.
D. Half-duplex Ethernet has lower effective throughput.
E. Half-duplex Ethernet operates in an exclusive collision domain.
3. [单选题]TCP23是（）协议端口号；UDP69是（）端口号；TCP80是（）端口号。
A. TELNET FTP HTTP
B. FTPT FTP HTTP
C. TELNET TFTP HTTP
D. TELNET DNS HTTP
4. [单选题]对于路由表，下列说法中正确的是：（）
A. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示RIP发现的路由，因为RIP协议的优先级更高
B. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示OSPF发现的路由，因为OSPF协议的优先级更高
C. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示RIP发现的路由，因为RIP协议的花费值（metric）更小
D. 在缺省的情况下，如果一台路由器同时运行了RIP和OSPF两种动态路由协议，则在路由表中只会显示OSPF发现的路由，因为OSPF协议的花费值（metric）更小
5. [单选题]RIP协议负载均衡的路径数量为（）
A. 无限制
B. 最多4条
C. 最多5条
D. 最多6条
