Consider interphase mass transfer of a species S between two immiscible liquids A and B. The interfacial mass transfer coefficient of S in liquid A is twice of that in liquid B. The equilibrium distribution of S between the liquids is given by $y_S^A = 0.5 y_S^B$, where $y_S^A$ and $y_S^B$ are the mole-fractions of S in A and B, respectively. The bulk phase mole-fraction of S in A and B is 0.10 and 0.02, respectively. If the steady-state flux of S is estimated to be 10 kmol h$^{-1}$ m$^{-2}$, the mass transfer coefficient of S in A is \(\underline{\hspace{2cm}}\) kmol h$^{-1}$ m$^{-2}$ (rounded off to one decimal place).