13.42 Consider two very large parallel plates with diffuse, gray surfaces. T₁ = 1000 K, £₁ = 1 T₂ = 500 K, £₂ = 0.8 Determine the irradiation and radiosity for the upper plate. What is the radiosity for the lower plate? What is the net radiation exchange between the plates per unit area of the plates?

13.42 Consider two very large parallel plates with diffuse, gray surfaces. T₁ = 1000 K, £₁ = 1 T₂ = 500 K, £₂ = 0.8 Determine the irradiation and radiosity for the upper plate. What is the radiosity for the lower plate? What is the net radiation exchange between the plates per unit area of the plates?