gif" width="36" height="36"></td>
     <td><p>The following additional information is associated with each label: </p>
       <p><strong>Opacity:</strong> A label can be made to appear partially transparent when it is displayed in the 3D window. This is useful when one structure, such as the skull, obstructs the view of another.</p>       
     <p><strong>Visibility:</strong> A label can be hidden from display, either in the 3D window or in all windows. Like transparency, this can be used to hide obstructin