With a Grid less than 15, and a Time of +52.833, what is the highest number of Laps?
CREATE TABLE "moto_gp_classification" (
  "rider" text,
  "manufacturer" text,
  "laps" real,
  "time" text,
  "grid" real
);
SELECT MAX("laps") FROM "moto_gp_classification" WHERE "grid"<15 AND "time"='+52.833';