Two black plates, each one meter square, are place parallel to each other in such a way that the radiation shape factor for the system is 0.4. If the plates are maintained at 8000C and 4000C respectively, determine the net radiant heat transfer between the plates, Also calculate the net heat exchange if the plates were infinite in size. Stephen Boltzmann constant = 5.67 ´ 10–8 W/m2K4