Name the fastest lap for piquet sports and silverstone
CREATE TABLE "results" (
  "round" text,
  "circuit" text,
  "date" text,
  "pole_position" text,
  "fastest_lap" text,
  "winning_driver" text,
  "winning_team" text
);
SELECT "fastest_lap" FROM "results" WHERE "winning_team"='Piquet Sports' AND "circuit"='Silverstone';