Question: What was the 2nd leg for team #1 River Plate?
SQL: SELECT "2nd leg" FROM "1-17282875-3" WHERE "Team #1" = 'River Plate';

Question: What was team number 2's Fluminense's 2nd leg?
SQL: SELECT "2nd leg" FROM "1-17282875-3" WHERE "Team #2" = 'Fluminense';