Three switches are connected to one anther via trunk ports.Assuming the default switch configuration,which switch is elected as the root bridge for the spanning-tree instance of vlan 1?（）

What is the default administrative distance of OSPF?（）

Which statement is true, as relates to classful or classless routing?（）

What is the subnetwork address for a host with the IP address 201.100.5.68/28?（）

A network administrator is planning a network installation for a large organization.The design requires 100 separate subnetworks,so the company has acquired a Class B network address.What subnet mask will provide the 100 subnetworks required, if 500 usable host addresses are required per subnet?（）

Which Cisco IOS diagnostics command can disrupt the operation of a router under high-load conditions?（）

The network administrator cannot to switch 1 over a telnet session,although the hosts attached to switch 1 can ping the interface Fa0/0 of the router.Given the information in the graphic and assuming that the router and switch2 are configured properly,which of the following commands should be issued on switch 1 to correct this problem?（）

Which address is the IPV6 all-RIP-routers muticast group address that is used by RIPng as the destaion address?（）

At which layer of the OSI model is RSTP used to prevent loops?（）

Which statement describes the rule of split horizon?（）