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 | To par | Margin of victory |
| --- | --- | --- | --- | --- |
| Feb 11, 1978 | Bob Hope Desert Classic | 69-67-67-67-69=339 | −21 | 2 strokes |
| Mar 29, 1981 | Sea Pines Heritage | 71-69-68-70=278 | −6 | 1 stroke |
| Jul 19, 1981 | The Open Championship | 72-66-67-71=276 | −4 | 4 strokes |
| Aug 30, 1981 | World Series of Golf | 68-69-71-67=275 | −5 | 1 stroke |
| Oct 4, 1981 | Texas Open | 67-66-70-63=266 | −14 | Playoff |
| Mar 20, 1983 | USF&G Classic | 69-67-69-69=274 | −14 | 3 strokes |
Question:
On what Date is the Winning Score 71-69-68-70=278?
Answer:
Mar 29, 1981