In which stage of a star's life cycle, does gravity and fusion become balanced, and an adult star forms? A. Main-sequence
B. Red supergiant
C. Protostar
D. White dwarf

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.