1. For this science fair project, the independent variable is the window of time allotted for monitoring the passing vehicles. The dependent variable is the average vehicle speed, volume of traffic and rate of traffic flow. This is determined by first recording the flow of traffic with the video camera, and carefully reviewing the recording. The constants (control variables) are the chosen location, the day of observation and the viewing range and angle of the video camera. 2. An elevated location is chosen along a highway. The video camera is set up using  the stand and adjusted so that a .....