单项选择题 Which command will show the MAC addresses of stations connected to switch ports?（）

单项选择题 QoS policies are applied on the switches of a LAN. Which type of command will show the effects of the policy in real time?（）

单项选择题 How many subnets can be gained by subnetting 172.17.32.0/23 into a /27 mask, and how many usable host addresses will there be per subnet?（）