In a system made up of a pipe, where the flow is presented vertically and ascending, having a diameter of 300 mm in the lower part, while in the upper part, it has a diameter twice that of the beginning, and with a separation height between the initial and final diameter of 4.5 m, water flows at a rate of 0.18 m^3/s, and the pressure at the initial point is 45 kPa, determine the pressure at the outlet of the pipe.