user: Question: On what date was the tournament played that eneded with a winning score of +6 (74-71-70-71=286) and margin of victory of 2 strokes, and with Arnold Palmer as the runner-up?
Columns: ['Date', 'Tournament', 'Winning score', 'Margin of victory', 'Runner(s)-up']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Jun 14, 1981', 'Peter Jackson Champions', '–12 (67-68-69=204)', 'Playoff', 'Gene Littler']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Runner(s)-up" = 'Arnold Palmer' AND "Margin of victory" = '2 strokes' AND "Winning score" = '+6 (74-71-70-71=286)';