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?（）

If all OSPF routers in a single area are configured with the same priority value,what value dose a router use for the ODPF router ID in the absence of a loopback interface?（）

How are VTP advertisements delivered to switches across the network?（）

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

Which IPsec security protocol should be used when confidentiality is required?（）

Which encapsulation type is a Frame Relay encapsulation type that is supported by Cisco routers?（）

When you are troubleshooting an ACL issue on a router,which command can help you to verify which interfaces are affected by the ACL?（）

Which cisco ios command can help to determine the timing of various debug events,relative to each other,when you are debugging a complicated router issue?（）

Which pairing reflects a correct protocol-and-metric relationship?（）

An employee of ABC company has move to an office on a different floor. Although the administrator is able to telnet to all of the routers,the address of Switch F is needed in order to verify that the employee remains in the same VLAN.Which action could be used by the administrator to find the IP address of Switch F?（）