Which rider had fewer than 10 laps for the Aprilia manufacturer, finishing in retirement?
CREATE TABLE "250cc_classification" (
  "rider" text,
  "manufacturer" text,
  "laps" real,
  "time_retired" text,
  "grid" real
);
SELECT "rider" FROM "250cc_classification" WHERE "laps"<10 AND "manufacturer"='aprilia' AND "time_retired"='retirement';