  The images of relativistic jets from extragalactic sources produced by
gravitational lensing by galaxies with different mass surface density
distributions are modeled. In particular, the following models of the
gravitational lens mass distribution are considered: a singular isothermal
ellipsoid, an isothermal ellipsoid with a core, two- and three-component models
with a galactic disk, halo, and bulge. The modeled images are compared both
between themselves and with available observations. Different sets of
parameters are shown to exist for the gravitationally lensed system B0218+357
in multicomponent models. These sets allow the observed geometry of the system
and the intensity ratio of the compact core images to be obtained, but they
lead to a significant variety in the Hubble constant determined from the
modeling results.
