Whitehouse, Patricia, 1958- <br/><br/>
Things that balance (Construction forces discovery library) 

 -  Rourke, Pub.,  c2007 
 - p. cm. 
<br/><br/> Explains what it means to balance, and looks at some of the things that balance on a construction site, including a sawhorse, ladder, scissor lift, and others. 
<br/><br/><label>ISBN: </label>1600441947 
<br/><br/><label>Dewey Class. No.: </label>531