A heat lamp emits infrared radiation whose rms electric field is Erms = 3600 N/C. (a) What is the average intensity of the radiation? (b) The radiation is focused on a person's leg over a circular area of radius 5.0 cm. What is the average power delivered to the leg? (c) The portion of the leg being radiated has a mass of 0.31 kg and a specific heat capacity of 3500 J/(kg·C°). How long does it take to raise its temperature by 2.1 C°? Assume that there is no other heat transfer into or out of the portion of the leg being heated.