Analyzing Ci A new school is being built and the archi- tects have planned a planetarium for the science wing. A planetarium is a specially designed room with a domelike ceiling where such things as star groupings, movement of the planets, and rotation and revolution of Earth are simulated and studied. A door will lead from the hall into the planetarium. Once a program has begun, the room must be in total darkness and the hall door should not be opened. Since the planetarium door cannot be locked because of fire safety rules, the Plane- tarium Director wants two lights in the hall-
