1. A television camera crew is setting up a new studio for filming the evening news. The light in the studio is very important for a quality picture. The crew finds that the brightness (B) of a light varies directly with the
intensity (I) of the light and inversely as the square of the distance (D) from the light. Brightness (B) is
measured in light energy per unit and intensity (I) is measured in candle power. At a distance of 20 feet, a
light meter gives a reading of 5 energy units for a 50-candle power lamp.
a. Determine the constant of variation. 1a. (2)
b. Find the reading of a 130-candle power lamp at a distance of 13 feet.