单项选择题
A.hello timer
B.BPDU timer
C.Forward_delay timer
D.Max_age timer
E.Dead timer
F.Wait timer
多项选择题 Given the above diagram and assuming that STP is enabled on all switch devices， which twostatements are true？（）
问答题 Refer to the output shown on switch SW1 below： Warning： Spantree port fast start should only be enabled on ports connected to a single host.Connecting hubs， concentrators， switches， bridges， etc. to a fast start port can cause temporaryspanning tree loops. Use with caution. Spantree ports 4/1-24 fast start enabled. What command could you enter to reproduce this output？
问答题 Refer to the output shown on switch SW1 below： VLAN 1 bridge priority set to 8192. VLAN 1 bridge max aging time set to 20.VLAN 1 bridge hello time set to 2. VLAN 1 bridge forward delay set to 15. Switch is now the root switch for active VLAN 1. What command would you enter to reproduce this output？