  We theoretically investigate the equation of state and Tan's contact of a
non-degenerate three dimensional Bose gas near a broad Feshbach resonance,
within the framework of large-$N$ expansion. Our results agree with the
path-integral Monte Carlo simulations in the weak-coupling limit and recover
the second-order virial expansion predictions at strong interactions and high
temperatures. At resonance, we find that the chemical potential and energy are
significantly enhanced by the strong repulsion, while the entropy does not
change significantly. With increasing temperature, the two-body contact
initially increases and then decreases like $T^{-1}$ at large temperature, and
therefore exhibits a peak structure at about $4T_{c0}$, where $T_{c0}$ is the
Bose-Einstein condensation temperature of an ideal, non-interacting Bose gas.
These results may be experimentally examined with a non-degenerate unitary Bose
gas, where the three-body recombination rate is substantially reduced. In
particular, the non-monotonic temperature dependence of the two-body contact
could be inferred from the momentum distribution measurement.
