What is the area located in Rhode Island with more than 38 sq mi area?
CREATE TABLE "islands_under_square_miles_km" (
  "island_s_name" text,
  "area_sq_mi" real,
  "area_km_2" real,
  "location" text,
  "population_2000" text
);
SELECT AVG("area_km_2") FROM "islands_under_square_miles_km" WHERE "location"='rhode island' AND "area_sq_mi">38;