What is the agg when the seconf leg is 58-75?
CREATE TABLE "first_qualifying_round" (
  "team_num1" text,
  "agg" text,
  "team_num2" text,
  "1st_leg" text,
  "2nd_leg" text
);
SELECT "agg" FROM "first_qualifying_round" WHERE "2nd_leg"='58-75';