Water is flowing through a pipe having diameter $500$mm and $300$mm at the bottom and upper end respectively. The intensity of pressure at the bottom is $30\mathrm{.}558$N$/$cm$2$ and pressure at the upper end is $16\mathrm{.}35$N$/$cm$2.$ Determine the difference in datum head if the rate of flow through the pipe is $66$liter$/$sec$.$ with the aid of a diagram determine the direction of flow.