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The Einstein ring gravitational lens has been studied with the VLA at 5, 8, 15, and 22~GHz. The new data at 15 and 22~GHz indicates that the spectra of the two compact components are flat. This suggests that the two compact components are images of the radio core of an extragalactic radio source, so the possibility of variability in MG1131+045 should not be excluded. Faraday rotation and depolarization ratios across the image are computed from the linearly polarized emission detected at 5 and 8~GHz. We find an asymmetry in the depolarization. The variations in the depolarization can be reconstructed by a model consisting of a lens with an elliptical gravitational potential and a radio source with a core, one-sided jet, and two extended radio lobes.