$$\matrix{ {[A]} & \to & {[B]} \cr {{\mathop{\rm Reactant}\nolimits} } & {} & {{\mathop{\rm Product}\nolimits} } \cr } $$

If formation of compound $$[\mathrm{B}]$$ follows the first order of kinetics and after 70 minutes the concentration of $$[\mathrm{A}]$$ was found to be half of its initial concentration. Then the rate constant of the reaction is $$x \times 10^{-6} \mathrm{~s}^{-1}$$. The value of $$x$$ is ______________. (Nearest Integer)