What is the Population of the group that has a Height (m) of 15 and an Area (ha) of 00017 17?
CREATE TABLE "main_list" (
  "island" text,
  "group" text,
  "area_ha" text,
  "population" text,
  "height_m" real
);
SELECT "population" FROM "main_list" WHERE "height_m"=15 AND "area_ha"='00017 17';