Two lines in a horizontal stack panel? (WPF)

Question

I have a stack panel (contains four fractions):

(Fractions are just text with new lines and hyphens.) If I add a fifth, it will go to the right of 10/12 instead of forming a second line.

How do I configure a StackPanel to overflow on the second line (and stay within the StackPanel) rather than overflow invisibly?

Markup:

<StackPanel Name="_fractionContainer" Width="700" Height="600" Orientation="Horizontal" Margin="8, 8, 8, 8" Background="White" /> 

Answer 1

Use the cover bar instead

 <WrapPanel Name="_fractionContainer" Orientation="Horizontal" ...>