Consider the variation of the effective index of the optical modes of a multimode silica fiber with the normalised frequency (V number), at an operating wavelength of 1.55 mm, as shown the figure below. Effective index, n. 1.440- 1.440 1.440 1.445 HEH ME Ma Normalised frequency, V WA TM (a) Determine the maximum Radius (Rmax) of the fiber by assuming that it supports only seven (4) propagating modes. (c) Estimate the maximum fiber radius (Rmax) for single mode condition and the propagation constant of the fundamental mode at the above diameter.