what is the height (m) when the birth date is 1968-07-01?
CREATE TABLE "sortable_list_of_competitors_with_s_kipp" (
  "nation" text,
  "birth_date" text,
  "height_m" text,
  "weight_kg" text,
  "world_rank" text
);
SELECT "height_m" FROM "sortable_list_of_competitors_with_s_kipp" WHERE "birth_date"='1968-07-01';