2. Most of the infrared (IR) that we experience comes from the thermal radiation of the objects around us. For the following objects, (a) calculate their temperature in kelvin and (b) using the Wien's law, find the a. = 2.9 103(m.K) / (K) , assuming each object radiates like a black body. (i) a person with a body temperature of = 37 ; (ii) a sidewalk on a hot summer day, with a surface temperature of = 45 ; and (iii) a building with an average surface temperature of = 20. (Note that = + 273). (c) To which region on the electromagnetic spectrum do these wavelengths belong?