Over continental regions, the number density (n = count of particles per volume of air) of particles with radius between R-0.5AR and R+0.5AR can be approximated by: n(r) = Answer: CAR

R4 for particles larger than 0.2 µm, and for small AR. Constant c depends on the total concentration of particles. This distribution, called the Junge distribution. If c=6×108 μm³ m³ calculate how many CCN there would be between 1.2 and 1.3 μm in 1 m³.