user: Question: what is the result when extra is 4 x 100 m relay and the year is later than 1971?
Columns: ['Year', 'Tournament', 'Venue', 'Result', 'Extra']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1971.0, 'European Indoor Championships', 'Sofia , Bulgaria', '2nd', '4 x 200 m relay']
SQL:

assistant: SELECT "Result" FROM "Table" WHERE "Extra" = '4 x 100 m relay' AND "Year" > 1971.0;