多项选择题
A. Full-duplex Ethernet uses CSMA/CD to prevent collisions.
B. Half-duplex Ethernet uses a loopback circuit to detect collisions.
C. A full-duplex Ethernet card allows 20Mbps for data transmission.
D. Full-duplex Ethernet makes use of two pairs of wires for data.
E. An Ethernet hub can operate both half and full duplex simultaneously.
单项选择题 On a half-duplex Ethernet LAN, two hosts attempt to send data simultaneously,resulting in a collision. Following this collision, what will the hosts do?（）
多项选择题 What is the IEEE standard associated with Gigabit Ethernet?（）
多项选择题 Which of the following can lead to the contribution of LAN traffic congestion?（）