Fish breath the dissolved air in water through their gills. Assuming the partial pressures of oxygen and nitrogen in air to be $0\mathrm{.}20$atm and $0\mathrm{.}80$atm, respectively, calculate the mole fractions of oxygen and nitrogen in water at $298K.$ Henry's law constant of oxygen and nitrogen are $0\mathrm{.}0013mo\frac{l}{L}.$atm and $0\mathrm{.}00068mo\frac{l}{L}.$atm respectively. Assume the density df water is $1\frac{g}{m}l.$