HTML uses codes to define many colors. Instead of white use the color #CCFFCC to define the background color of your table.

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<title>Trees</title>
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<h1>About Trees</h1>

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<p><b>Learning About Trees.</b>
Take a <i>camera, a sketchbook, and a field guide</i>
with you when you go on a hike.  
Look closely at the trees.  Use the field guide to identify the trees.  
Use your sketchbook to draw pictures of the trees.  Take some 
pictures with the camera.</p>

<img src='elmleaf.jpg' 
width='200' height='150' alt='Elm Leaf'>

<p><a href='http://www.arboretum.harvard.edu/'>Click here 
to visit the Arnold Arboretum website</a>
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