Calculate the solubility product of $Co_2[Fe(CN)_6]$ in water at $25^\circ$C. Given, conductivity of saturated solution of $Co_2[Fe(CN)_6]$ is $2.06 \times 10^{-6}$ $\Omega^{-1}$ $cm^{-1}$ and that of water used is $4.1 \times 10^{-7}$ $\Omega^{-1}$ $cm^{-1}$. The ionic molar conductivities of $Co^{2+}$ and $[Fe(CN)_6]^{4-}$ are $86.0$ $\Omega^{-1}$ $cm^2$ $mol^{-1}$ and $444.0$ $\Omega^{-1}$ $cm^2$ $mol^{-1}$, respectively.