Every year at the "proffentap"$-$evening in the Recup traditionally consumes many barrels of beer. A typical beer keg has an internal diameter of$36$cm and an internal height of$55$cm and contains$50$liter of beer. The barrel is connected to a tapping installation as shown in the figure below. The barrel itself is in the cellar and the tap outlet is located$3$meters higher. The pipe that connects the tap to the barrel has a diameter of$9$mm up to the tap, which has an outlet diameter of$5$mm has. A gas bottle with CO$2$keeps the absolute pressure at the surface of the beer constant$1,5$bar. Since beer consists largely of water, you can use the thermodynamic properties of water.

CO 4 9mm 4 5mm 3m