Animations Silverlight

    xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation' 
    xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'
    xmlns:d='http://schemas.microsoft.com/expression/blend/2008' 
    xmlns:mc='http://schemas.openxmlformats.org/markup-compatibility/2006' 
    mc:Ignorable='d' 
    d:DesignWidth='640' 
    d:DesignHeight='480'>
    
          Height="20" HorizontalAlignment="Left" />
          Content="Start Animations" Width="100">
      
        
          
            
              
                                  Storyboard.TargetName="rect3" Storyboard.TargetProperty="Width"
                  From="20" To="400" Duration="0:0:10" SpeedRatio="0.5" />