In a data communication system, which transport media can be described as following: Has two classes: single mode and multiple mode; with higher transmit rate; with the best reliability

A．radio channel

B．fiber optic cable

C．twisted-pair cable

D．coaxial cable

[单选题]A．(72) is a data communication system that allows a number of independent devices to communications directly with each other in a limited geographic area.A．LANB．WANC．InternetD．Ethernet

[单选题]Which of the following strategies belongs to communication strategy?A.When

[单选题]Which of the following statements is NOT the feature of oral communication?

[问答题]数据通信（Data Communication）

[单选题]Which of the following system adopts a three-tier classification system:A.R

[单选题]Which country's way of communication made use of visible signs?A． FrenchB． RomanC． AfricanD． American

[单选题]Which of the following statements its true according to the text?A．) Doctors will be held guilty if they risk their patients' death.B．) Modern medicine has assisted terminally iii patients in painless recovery.C．) The Court ruled that high-dosage pa

[单选题]_______control system is one in which the control action is independent of the output.A．Feed backB．Negative feed backC．Close loopD．Open loop

[单选题]Which system should be supplied to obtain the best efficiency and lowest emissions?A．Lean combustion principleB．Fuel oil systemC．Electrical control systemD．Electronic control system

[单选题]When the system upon which a transport entity is running fails and subsequently restarts, the(66)information of all active connections is lost. The affected connections become half-open, as the side that did not fail does not yet realize the problem.