powe 23.13 A small circular hole is to be drilled in the surface of a large, hollow, spherical enclosure maintained at 2000 K. If 100 W of radiant energy exits through the hole, determine (a) the hole diameter, (b) the number of watts emitted in the visible range from 0.4 and 0.7 um, (c) the ultraviolet range between 0 and 0.4 mm, and (d) the infrared range from 0.7 to 100 um