Refer to the exhibit and the partial configuration of switch SW_A and SW_B. STP is configured on all switches in the network. SW_B receives this error message on the console port：

00：06：34： %CDP-4-DUPLEX_MISMATCH： duplex mismatch discovered on FastEthernet0/5 （not half  duplex）， with SW_A FastEthernet0/4 （half duplex） ， with TBA05071417（Cat6K-B） 0/4 （half duplex）.
 What would be the possible outcome of the problem？（）

多项选择题WhichtwostatementsaboutthevariousimplementationsofSTParetrue？（）

A.mon Spanning Tree maintains a separate spanning-tree instance for each VLAN configured in the network.
B.The Spanning Tree Protocol （STP） is an evolution of the IEEE 802.1w standard.
C.Per-VLAN Spanning Tree （PVST） supports 802.1Q trunking.
D.Per-VLAN Spanning Tree Plus（PVST+） is an enhancement to 802.1Q specification and is supported only on Cisco devices.
E.Rapid Spanning Tree Protocol （RSTP） includes features equivalent to Cisco PortFast， UplinkFast， and BackboneFast for faster network reconvergence.
F.Multiple Spanning Tree （MST） assumes one spanning-tree instance for the entire Layer 2 network， regardless of the multiple number of VLANs

单项选择题Refer to the exhibit. For what purpose is the command show ip cef used？（）

A.to display rewritten IP unicast packets
B.to display ARP resolution packets
C.to display ARP throttling
D.to display TCAM matches
E.to display CEF-based MLS lookups
F.to display entries in the Forwarding Information Base （FIB）

单项选择题Refer to the exhibit. Which statement is true about the output？（）

A.The port on switch CAT1 is forwarding and sending BPDUs correctly.
B.The port on switch CAT1 is blocking and sending BPDUs correctly.
C.The port on switch CAT2 is forwarding and receiving BPDUs correctly.
D.The port on switch CAT2 is blocking and sending BPDUs correctly.
E.The port on switch CAT3 is forwarding and receiving BPDUs correctly.
F.The port on switch CAT3 is forwarding， sending， and receiving BPDUs correctly.

单项选择题Refer to the exhibit.  What does the command channel-group 1 mode desirable do？ （）

A.enables LACP unconditionally
B.enables PAgP only if a PAgP device is detected
C.enables PAgP unconditionally
D.enables Etherchannel only
E.enables LACP only if a LACP device is detected

多项选择题Refer to the exhibit. Initially， LinkA is connected and forwarding traffic. A new LinkB is then attached between SwitchA and HubA.  Which two statements are true about the possible result of attaching the second link？（）

A.The switch port attached to LinkB will not transistion to up.
B.One of the two switch ports attached to the hub will go into blocking mode when a BPDU is received.
C.Both switch ports attached to the hub will transition to the blocking state.
D.A heavy traffic load could cause BPDU transmissions to be blocked and leave a switching loop. 
E.The switch port attached to LinkA will immediately transition to the blocking state.