A flat plate made of cast iron is exposed to a solar flux of $600\; W/m^{2}$ at an ambient temperature of $25^{\circ}C$. Assume that the entire solar flux is absorbed by the plate.
Cast iron has a low temperature absorptivity of $0.21$. Use Stefan-Boltzmann constant $= 5.669 \times 10^{-8}\; W/m^{2}- K^{4}$. Neglect all other modes of heat transfer except radiation.
Under the aforementioned conditions, the radiation equilibrium temperature of the plate is _____________$^{\circ}C$ (round off to the nearest integer).