1. The problem statement, all variables and given/known data The particles of an ink blob dropped into a large container of water diffuse outward and obey the radial diffusion equation: dn/dt = (D/r2) (d/dr) (r2* (dn/dr) ) where n(r,t) is the density of ink particles at point r at time t and D is the diffusion constant. Verify, by direct differentiation that: ns = N*(1 / (4*pi*D*t) )3/2 * er2/4Dt is a solution of this equation and satisfies the condition that the total number of ink particles is N for any value of t. 2. Relevant equations 3. The attempt at a solution I have no idea?