A pipe network connects junctions A, B, C, and D as shown in Figure PS.31. All pipes have a Hazen Williams coefficient of 110 and the ocher pipe and flow parameters are as follows: A A-B: L = 1000 m,...

A pipe network connects junctions A, B, C, and D as shown in Figure PS.31. All pipes have a Hazen Williams coefficient of 110 and the ocher pipe and flow parameters are as follows:

A A-B: L = 1000 m, d = 0.5 m, Q = 10001/s;

B-C: L = 500 m, d = 0.4 m, Q = 5001/s;

C-D: L = 2000 m, d = 0.3 m, Q = 220 1/s.

Water can be added or subtracted at any of the junctions in order to achieve the required flows and the flow direction is from A to D with no backward flow at any junction. If minor losses are negligible, and the minimum allowable pressure anywhere in the line is 100 kN/, what must be the pressure at point A and what is the elevation of the hydraulic grade line there?