Adsorption of phenol from its aqueous solution on to fly ash obeys Freundlich isotherm. At a given temperature, from 10 mg g$$^{-1}$$ and 16 mg g$$^{-1}$$ aqueous phenol solutions, the concentrations of adsorbed phenol are measured to be 4 mg g$$^{-1}$$ and 10 mg g$$^{-1}$$, respectively. At this temperature, the concentration (in mg g$$^{-1}$$) of adsorbed phenol from 20 mg g$$^{-1}$$ aqueous solution of phenol will be ______.

Use: $$\log_{10} 2 = 0.3$$