What is the fewest number of silver medals received by a nation who received 40 bronze medals and more than 42 gold medals?
CREATE TABLE "medal_table" (
  "rank" text,
  "nation" text,
  "gold" real,
  "silver" real,
  "bronze" real,
  "total" real
);
SELECT MIN("silver") FROM "medal_table" WHERE "bronze"=40 AND "gold">42;