What is the height for the player in 1968-72?
CREATE TABLE "l" (
  "player" text,
  "no_s" text,
  "height_in_ft" text,
  "position" text,
  "years_for_rockets" text,
  "school_club_team_country" text
);
SELECT "height_in_ft" FROM "l" WHERE "years_for_rockets"='1968-72';