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By: David J. Smith, 

Age: 6+

ISBN: 9781894786348

Keywords: 
astronomy,  biodiversity,  educational,  energy,  food,  history of earth,  inventions,  learning,  life expectancy,  natural resources,  planets,  population,  rain,  solar system,  time,  water cycle,  wealth,  world,  world history,  world population,