1. Suppose that you observe a distant source of a particular intensity. If you
now increase your distance from the source by a factor of 10, by what factor does
the intensity of the source decrease?
2. If you decrease your distance from a light source from 100 meters to 60
meters, by what factor does the observed intensity go up?
3. By what factor do I have to decrease the distance between me and a source for
the apparent intensity to go up by a factor of 10?