Science explorer.  Chapters 1-5. 

 - New Jersey:  Person Prentice Hall,  n.d. 
 - xx, 358 p. 
<br/><br/>Includes index. 
<br/><br/><label>ISBN: </label>0-13-190531-7 
<br/><br/><label>Dewey Class. No.: </label>372.358 SCI