Ablock of mass m2 on arough horinzontal surfaceis connected to aball of mass m1 by alight weight cord over alight weight friction pulley as shownin figure .aforce of magnitude f at an angle

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.