For the phase transformation     S(rhombic) ~ S(monoclinic),   ${\mathrm{\Delta }}_f H^{\circ }$ (S, monoclinic) $=0.33 \mathrm{kJ}{ \mathrm{mol}}^{-1}$,$S^0$ (S, monoclinic) $=32.6 {\mathrm{JK}}^{-1}{ \mathrm{mol}}^{-1}$ and $S^{\circ }$  ( S, rhombic)=$31.8 {\mathrm{JK}}^{-1}{ \mathrm{mol}}^{-1}$.The temperature at which the above transformation is in equilibrium is