1.In a constant-head permeability test, a sample of sand 12cm longand 8 cm in diameter discharged 1.5 X 10^-3 cubic meters of waterin 10 minutes. The head difference in two manometers A and Blocated at 10mm and 110mm, respectively, from the bottom of thesample is 20mm. Determine the hydraulic conductivity of thesand.
2.A line passes through the points (20m, 16m) and (-1m, -4m). Determine the perpendicular distance d from the line to the origin O of the system of coordinates.