Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Date | Tournament | Winning score | Margin of victory | Runner(s)-up |
| --- | --- | --- | --- | --- |
| Oct 2, 2011 | SAS Championship | −11 (66-69-70=205) | 1 stroke | John Huston , Jeff Sluman |
| Feb 19, 2012 | ACE Group Classic | −20 (64-62-70=196) | 5 strokes | Bernhard Langer |
| Jun 30, 2013 | Constellation Senior Players Championship | −19 (71-63-63-64=261) | 2 strokes | Fred Couples , Duffy Waldorf |
| Jul 14, 2013 | U.S. Senior Open | −13 (67-73-64-63=267) | 5 strokes | Fred Funk |
| Oct 27, 2013 | AT&T Championship | −13 (65-71-67=203) | Playoff | Bernhard Langer |
Question:
Which Margin of victory has a Tournament of u.s. senior open?
Answer:
5 strokes