146. Solving a chemistry problem

2. Calculate the average radius of the hydrosol particles of the polystyrene latex, according to the data obtained with the nephelometer: the height of the illuminated part of the standard and unknown sol are h 1 = 8 × 10 -3 m and h 2 = 18 · 10 -3 m, respectively; the average radius of the particles of the standard sol r 1 = 88⋅10 -9 m. Concentrations of standard and unknown sols are equal.