Balance the equations with the correct coefficient on the lines. __NaBr+__Cl2 ->__Br2+__NaCl

It's because 3 if it was 10 it wouldn't look right do it goes up to 4d

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.