Michael discovers that a fish breathes less often in cool water. He correctly hypothesizes that A. the fish slows down in cool water, and does not need as much oxygen. B. the fish is eating, and does not have time to breathe as much. C. the fish is sleeping, and does not need as much oxygen. D. there is less oxygen in cool water, so the fish breathes slowly.

The answer is atmosphere. there are four spheres of the earth: 1. geosphere (from greek word 'geo' = ground), 2. hydrosphere (from greek word 'hydro' = water), 3. biosphere (from greek word 'bio' = life), and 4. atmosphere (from greek word 'atmo' = air). a magnetosphere is a region of space around astronomical objects controlled by the magnetic field of that object. through the process of elimination, since lightning is present in the air, it can be found in the atmosphere.