At what temperature (in Kelvin) will the diffusion coefficient for the diffusion of species A in metal B have a value of 6.48 × 10-15 m2/s, assuming values of 4.0 × 10-5 m2/s and 230,000 J/mol for D0 and Qd , respectively?

When you see distant streetlights through smog, they look dimmer and redder than they do normally. but when you see the same streetlights through fog or falling snow, they look dimmer but not redder. use your knowledge of the interstellar medium to discuss the relative sizes of the particles in smog, fog, and snowstorms compared to the wavelength of light.