You are given a liquid and are asked to find its viscosity. Its density is known to be 0.97 g/cm^3. You place the fluid in an open vessel to which a 20 cm long vertical tube with an inside diamter of 2 mm, is attached to the bottom. When the depth of the liquid in the container is 6 cm, you find that it drains out through the at a rate of 2.5 cm^3/s. If the diameter of the open vessel is much laarger than that of the tube and friction loss from the vessel to the tube is negligible, what is the fluid viscosity?