What is the total number of population in the year 2005 where the population density 35.9 (/km 2)?
CREATE TABLE "references" (
  "inegi_code" real,
  "municipality" text,
  "municipal_seat" text,
  "area_km_2" text,
  "population_2005" real,
  "population_density_km_2" text,
  "human_development_index_2000" text
);
SELECT COUNT("population_2005") FROM "references" WHERE "population_density_km_2"='35.9';