The diameters of a buble at the surface of a lake is 4 mm and at the bottom of the lake is 1 mm. If atmospheric pressure is 1 atm, what is the depth of the lake ? The density of lake-water and Hg are 1.0 gm/ml and 13.6 gm/ml, respectively. Assume that temperature of lake water is equal to that of atmosphere.Also neglect the contribution of pressure due to surface tension.