1.    The underside of a smoky layer 14m x 9m is radiating like a flat, isotropic plate at 510°C to...

1.    The underside of a smoky layer 14m x 9m is radiating like a flat, isotropic plate at 510°C to the floor of a compartment 2.15m below.  The mean emissivity is 0.41 and the floor is homogenous/flat plate at 35°C.  What is the rate of heat transfer from the smoky layer to the floor?