Fluid Mechanics

In to a vessel containing pure water a clean glass tube of radius $3.6 \times 10^{-4} \mathrm{~m}$ is held vertically with 12 cm of the tube above the water level. Now the capillary tube is moved down in to the water so that only 2 cm of its length is above the water surface. Angle of contact $\Theta$ at this position is (given surface tension of water $=7.2 \times 10^{-2} \mathrm{Nm}^{-1}$ and $g=10 \mathrm{~ms}^{-2}$ )