CREATE TABLE "polish_voivodeships_and_separate_cities_" (
  "abbreviation" text,
  "voivodeship" text,
  "capital" text,
  "area_km_1998" text,
  "population_1980" text,
  "no_of_cities" real,
  "no_of_communes" real
);

Question: What's the area of the voivodenship with 51 communes?
SQL: SELECT "area_km_1998" FROM "polish_voivodeships_and_separate_cities_" WHERE "no_of_communes"=51;

Question: How big (in km2) is the voivodenship also known by the abbreviation KN?
SQL: SELECT "area_km_1998" FROM "polish_voivodeships_and_separate_cities_" WHERE "abbreviation"='kn';

Question: How many people lived in the voivodenship whose capital is Siedlce in the year of 1980?
SQL: SELECT "population_1980" FROM "polish_voivodeships_and_separate_cities_" WHERE "capital"='Siedlce';

Question: How many different voivodenship have 747 900 citizes?
SQL: SELECT COUNT("voivodeship") FROM "polish_voivodeships_and_separate_cities_" WHERE "population_1980"='747 900';