在表student中增加一列address，将该列置于phone字段之后，使用语句（ ）。 A: ADD TABLE student(address varchar(20))； B: ADD TABLE student ALTER(address varchar(20))； C: ALTER TABLE student ADD address varchar(20)； D: ALTER TABLE student ADD address varchar(20) AFTER phone；

The hardware address of a computer on a LAN can also be called a MAC address because ().

Every NIC has a unique address that consists of a 48-digit hexadecimal value. this address is called MAC address.（ ）

MAC broadcast address is ( ). A: FF-FF-FF-FF-FF-00 B: 255.255.255.255 C: FF-FF-FF-FF-FF-FF D: 255.255.255.0

以下哪个命令用于查看交换机MAC地址表?( ) A: switchport mode access B: show interface C: show mac-address-table D: switchport mode trunk

在二层交换机中察看MAC地址表的命令是( )。 A: show mac-address-table B: show mac-port-table C: show address-table D: show L2-table

​MAC 地址表是交换机转发网络中数据依据，在交换机中，查看交换机 MAC 地址表的命令是​​​ A: show mac-port-table B: show mac-address-table C: show address-table D: show L2-table

‍MAC 地址表是交换机转发网络中数据依据，在交换机中，查看交换机 MAC 地址表‎‍的命令是‎‍‎ A: show mac-port-table B: show mac-address-table C: show address-table D: show L2-table

在二层交换机中察看转发查询表（即MAC地址表）的命令是？ A: show mac-address-table B: show mac-port-table C: show address-table D: show L2-table

What is stored in the ARP table of the Internet host? ( ) A: IP addresses B: MAC addressses C: the mapping of domain names to IP addressses D: the mapping of IP addresses to MAC addressses