What is the sum of Second, when Total is less than 70, when Premier is less than 20, and when First is greater than 18?
CREATE TABLE "number_of_participants" (
  "season" text,
  "premier" real,
  "first" real,
  "second" real,
  "total" real
);
SELECT SUM("second") FROM "number_of_participants" WHERE "total"<70 AND "premier"<20 AND "first">18;