  We present theoretical predictions for the equation of state of a
harmonically-trapped Fermi gas in the unitary limit. Our calculations rest on a
study of the equation of state of a uniform gas using three distinct
perturbation schemes, compared to Monte-Carlo results. We show that in
experiments the temperature can be usefully calibrated by making use of the
entropy, which is invariant during an adiabatic conversion into the
weakly-interacting limit of molecular BEC. We predict the entropy dependence of
the equation of state.
