1. [单选题]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? (Select all valid answers)
A. The destination host sends a request to the source for retransmission.
B. The jam signal indicates that the collision has been cleared.
C. The hosts will attempt to resume transmission after a time delay has expired.
D. An electrical pulse indicates that the collision has cleared.
E. The router on the segment will signal that the collision has cleared.
F. F. The hosts will do nothing, as the higher layers are responsible for data error correction and re-transmission.
2. [单选题]After working on a router, some problems arise and you wish to view the commands that you recently entered. Which IOS command opens the history buffer and displays the most recently entered commands?
A. Show history
B. Show buffers
C. Show typed commands
D. Show terminal buffer
E. Show command
F. F. None of the above
