What is the average round at which is the position of Tight End and Randy Bethel?
CREATE TABLE "nfl_draft" (
  "round" real,
  "pick" real,
  "player" text,
  "position" text,
  "school_club_team" text
);
SELECT AVG("round") FROM "nfl_draft" WHERE "position"='tight end' AND "player"='randy bethel';