  We report the continuum limits of the speed of sound, c_s, and the specific
heat at constant volume, c_v, in quenched QCD at temperatures of 2Tc and 3Tc.
At these temperatures, c_s is within 2-sigma of the ideal gas value, whereas
c_v differs significantly from the ideal gas. However, both are compatible with
results expected in a theory with conformal symmetry. We investigate effective
measures of conformal symmetry in the high temperature phase of QCD.
