The spectral emissive power E1 for a diffusely emitting surface is E1 = 0 for λ < 3 μm; E1 = 150 W/m2-μm for 3 < λ < 12 μm; E1 = 300 W/m2-μm for 12 < λ < 25 μm; E1 = 0 for λ > 25 μm. The total emissive power of the surface over the entire spectrum is
1
1250 W/m2
2
2500 W/m2
3
400 W/m2
4
5250 W/m2