Consider an opaque, diffuse surface whose spectral reflectivity varies with wavelength as shown. The surface is at 750 K, and irradiation on one side varies with wavelength as shown. The other side of the surface is insulated. Determine the total absorptivity of the surface. απ 0.52 Determine the total emissivity of the surface. × 0.9556 E Px 0.8 0.4 012 λ (um) 3 4 G₂ (W/m²μm) 500 0 0 1 2 3 4 5 678 λ (μm)