  We consider two-component fermions with a zero-range interaction both in two
and three dimensions and study their spectral functions of bulk and shear
viscosities for an arbitrary scattering length. Here the Kubo formulas are
systematically evaluated up to the second order in the quantum virial expansion
applicable to the high-temperature regime. In particular, our computation of
the bulk viscosity spectral function is facilitated by expressing it with the
contact-contact response function, which can be measured experimentally under
the periodic modulation of the scattering length. The obtained formulas are
fully consistent with the known constraints on high-frequency tail and sum
rule. Although our static shear viscosity agrees with that derived from the
kinetic theory, our static bulk viscosity disagrees. Furthermore, the latter
for three dimensions exhibits an unexpected non-analyticity of $\zeta\sim(\ln
a^2)/a^2$ in the unitarity limit $a\to\infty$, which thus challenges the
"crossover" hypothesis.
