A soap bubble, having radius of 1 mm, is blown from a detergent solution having a surface tension of \(2.5 × 10^{−2}N ∕ m\). The pressure inside the bubble equals at a point \(Z_0\) below the free surface of water in a container. Taking \(g = 10 m ∕ s^2\), density of water = \(10^3kg ∕ m^3\), the value of \(Z_0\) is