Los porqués de nuestro mundo 

 - Washington, D.C.  Charlotte, N.C.  National Geographic Society  Stampley Enterprises  c1993. 
 - 95 p.  col. ill.  28 cm. 
 - Colección Explora y aprende .
<br/><br/> Translation of: Why on earth?  Includes index. 
<br/><br/> Questions and answers present information on science topics, including human physiology, animal behavior, earth science, and natural science. 
<br/><br/><label>ISBN: </label>0915741482 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Science--Miscellanea--Juvenile literature.<br/>Preguntas y respuestas para niños--Literatura juvenil.<br/>Ciencia--Miscelánea--Literatura juvenil.<br/>Children's questions and answers--Juvenile literature.