A2.5Gb/s(OC-48orSTM-16)opticalsignalwithadispersiontoleranceof1200ps/nmgoesthroughfiberwith18ps/nm*kmofdispersion.Howmany15216-DCU-350equivalentsareneededforenoughcompensationaftertraveling100km?()

题目
A2.5Gb/s(OC-48orSTM-16)opticalsignalwithadispersiontoleranceof1200ps/nmgoesthroughfiberwith18ps/nm*kmofdispersion.Howmany15216-DCU-350equivalentsareneededforenoughcompensationaftertraveling100km?()

A.none

B.one

C.two

D.three

E.four