49. Solving a chemistry problem

Calculate the thickness of the diffusion ion layer λ, on the plate surface at 300 K in an aqueous solution, 1 liter of which contains 0.05 g NaCl and 0.01 g Ba(NO3)2 (indifferent electrolytes). The relative permittivity of the solution is 76.5. How many times will λ change if the solution is diluted 4 times with pure water?