Superman is standing 120 m horizontally away from Lois Lane. A villain throws a rock vertically downward
with a speed of 2.8 m/s from 14.0 m directly above
Lois. (a) If Superman is to intervene and catch the rock
just before it hits Lois, what should be his minimum
constant acceleration? (b) How fast will Superman be
traveling when he reaches Lois

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.