A mail carrier walked six blocks to the north, one block to the east, and then six blocks to the south. What was the mail carrier’s displacement? *

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.

Inner peace.. jk it's  a stable electron configuration