Three piezometers located 1000 m apart bottom in the same horizontal aquifer. piezometer a is due south of piezometer b and piezometer c is to the east of the line ab. the surface elevations of a, b, and c are 95, 110, and 135 m, respectively. the depth to water in a is 5 m, in b is 30 m, and in c is 35 m. determine the direction of ground-water flow through the triangle abc and calculate the hydraulic gradient.