Two narrow bores of diameters 3.0 mm and 6.0 mm are joined together to form a U-tube open at both ends. If the U-tube contains water, what is the difference in its levels in the two limbs of the tube ? Surface tension of water at the temperature of the experiment is 7.3 x 10^-2 Nm^-1. Take the angle of contact to be zero and density of water to be 1.0 x 10³ kgm^-3 (g = 9.8 ms^-2)