The heat is dissipated from the plate by convection and radiation into surroundings at 20°C. Take ε = 0.8, σ = 5.67*10**-8, and ho = 6 W/m**2.K. If the surface temperature of the plate is 50°C, the value of the heat flux from the plate is
309.71 W/m2
471.91 W/m2
394.93 W/m2
479.27 W/m2