What is the sum of Round, when Nationality is "United States", and when Pick is "125"?
CREATE TABLE "draft_picks" (
  "round" real,
  "pick" real,
  "player" text,
  "nationality" text,
  "school_club_team" text
);
SELECT SUM("round") FROM "draft_picks" WHERE "nationality"='united states' AND "pick"=125;