What was the 2nd leg score for the tie that had a 5-0 first leg score?
CREATE TABLE "second_round" (
  "team_1" text,
  "agg" text,
  "team_2" text,
  "1st_leg" text,
  "2nd_leg" text
);
SELECT "2nd_leg" FROM "second_round" WHERE "1st_leg"='5-0';