You take your dog for a 2.5 mile walk everyday. You start at your house, go around the block, then straight to the park and then back to your house. What is the total displacement of your walks everyday?

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A. they hold atoms  together with a molecule.its a force that exist between molecules. hope this .

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.