At a baseball game on a cool day a ticket holder hears the crack of the bat one-half second after watching the batter hit the ball. How far is home plate from where he is standing if the air temperature is 16°C?

The answer is water molecules are split.cellular respiration and photosynthesis are complement  reactions to each other. these are reverse reactions. in cellular respiration glucose and oxygen yield water and carbon dioxide. so, when respiration begins,  glucose molecules are split. in the opposite reaction - in photosynthesis, carbon dioxide and water yield glucose and oxygen. thus,  when respiration begins, water molecules are split.