  We calculate the detectability of the polarization of the cosmic microwave
background (CMB) as a function of the sky coverage, angular resolution, and
instrumental sensitivity for a hypothetical experiment. We consider the
gradient component of the polarization from density perturbations (scalar
modes) and the curl component from gravitational waves (tensor modes). We show
that the amplitude (and thus the detectability) of the polarization from
density perturbations is roughly the same in any model as long as the model
fits the big-bang-nucleosynthesis (BBN) baryon density and degree-scale
anisotropy measurements. The degree-scale polarization is smaller (and
accordingly more difficult to detect) if the baryon density is higher. In some
cases, the signal-to-noise for polarization (both from scalar and tensor modes)
may be improved in a fixed-time experiment with a smaller survey area.
