CREATE TABLE "table1_29289372_1" (
  "city_municipality" text,
  "population_2010" real,
  "area_km" text,
  "pop_density_per_km" text,
  "income_classification" text
);

Question: When 318676 is the population of 2010 and 1st class is the income classification what is the area in kilometers squared?
SQL: SELECT "area_km" FROM "table1_29289372_1" WHERE "income_classification"='1st Class' AND "population_2010"=318676;

Question: When itogon, benguet is the city/municipality and 1st class is the income classification how many measurements of population in 2010?
SQL: SELECT COUNT("population_2010") FROM "table1_29289372_1" WHERE "income_classification"='1st Class' AND "city_municipality"='Itogon, Benguet';

Question: When 82.74 is the area in kilometers squared what is the pop.density (per km2)?
SQL: SELECT "pop_density_per_km" FROM "table1_29289372_1" WHERE "area_km"='82.74';

Question: When 106 is the area in kilometers squared what is the city/municipality?
SQL: SELECT "city_municipality" FROM "table1_29289372_1" WHERE "area_km"='106';