下面RAID级别中，数据冗余能力最弱的是（　）
A.RAID5
B.RAID1
C.RAID6
D.RAID0

在Windows系统中监听发送给NT主机的陷入报文的程序是（ ）。
A.snmp.exe
B.mspaint.com
C.notepad.exe
D.snmptrap.exe

以下关于网络互联设备的选择的说法，不正确的是（）。
A.不同层次的互联设备实现互联的原理不同，一般来说选择设备不会影响网络的可维护性
B.网络互联设备包括网桥、交换机、路由器、网关等
C.第二层实现异构网络互联，选择网桥
D.在网络设计中，网络互联设备的选择十分重要。在不同的互联层次，应选择不同的互联设备。

使用RAID5,3块300G的磁盘获得的存储容量为（）
A.300G
B.450G
C.600G
D.900G

Anytime a host or a router has an IP datagram to send to another host or router, it has the（　）address of the receiver. This address is obtained from the DNS if the sender is the host or it is found in a routing table if the sender is a router. But the IP data gram must be（　） in a frame to be able to pass through the physical network. This means that the sender needs the （　）address of the receiver. The host or the router sends an ARP query packet. The packet includes the physical and IP addresses of the sender and the IP address of the receiver. Because the sender does not know the physical address of the receiver, the query is（　） over the network.Every host or router on the network receives and processes the ARP query packet, but only the intended recipient recognizes its IP address and sends back an ARP response packet.The response packet contains the recipient's IP and physical addresses. The packet is（请作答此空） directly to the inquirer by using the physical address received in the query packet.

A. multicast
B. unicast
C. broadcast
D. multiple unicast

影响光纤熔接损耗的因素较多，以下因素中影响最大的是（64）。
A.光纤模场直径不一致
B.两根光纤芯径失配
C.纤芯截面不圆
D.纤芯与包层同心度不佳