A round pipe of varying diameter carries petroleum from a wellhead to a refinery. At the wellhead the pipe\'s diameter is 51.3 cm and the flow speed of the petroleum is 12.5 m/s. At the refinery the petroleum flows at 6.87 m/s. What is the volume flow rate of the petroleum along the pipe and what is the pipe\'s diameter at the refinery?
volume flow rate:
________m^3/s
diameter
________cm