单项选择题 Which of the following LAN technology has a MAXIMUM range of 10,000 meters (6 miles)?（）

单项选择题 Which of the following is the purpose of QoS?（）

单项选择题 A network administrator needs to add an additional connection to a room. The administrator adds a new Ethernet switch and must connect it to an existing switch. Which cable type should be used to connect the two switches?（）