●Communication networks can be classified in terms of their physical arrangement or (73) Three common (73) are the star,bus,and ring.(73) A．structuresB．topologiesC．protocolsD．frames
●Communication networks can be classified in terms of their physical arrangement or (73) Three common (73) are the star,bus,and ring.
(73) A．structures
B．topologies
C．protocols
D．frames
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