An opaque surface, $2$ m by $2$ m $,$ is maintained at $400$ K and is simultaneously exposed to solar irradiation with $G=1200\frac{W}{m}2.$ The surface is diffuse and its spectral absorptivity is ${}_{}=0,0\mathrm{.}8,0,$ and $0\mathrm{.}9$ for $00\mathrm{.}5m,0\mathrm{.}5m1m,1m2m$ and $>2m$ respectively. Determine the absorbed irradiation, emissive power, radiosity, and net radiation heat transfer from the surface.