Alimestone rock is found in an arizona desert. the limestone is gray and has a fish fossil. what can scientists learn from the limestone?

That there was once water in that area

Well,what i learned was that unlike many other  endothermic  reactions,  photosynthesis  does not absorb energy as heat. instead, during plants absorb energy from sunlight to turn carbon dioxide and water into oxygen and glucose, which is a type of sugar molecule. the energy is stored in the glucose molecules, ready to be used when needed.