15. How many times will the total number of particles n 0 of the open-hearth furnace smoke decrease in 100 c after the coagulation begins? The average particle radius before the start of coagulation is r = 2⋅10 -8 m; particle concentration C = 1 · 10 -3 kg / m 3; density ρ = 2,2⋅10 3 kg / m 3; the Smoluchowski constant K = 3⋅10 -16 m 3 / s.