Question: What is the population in millions for 2011 where the HDI for 2011 is 0.453 (low)?
SQL: SELECT "Population (millions, 2011)" FROM "1-2155836-1" WHERE "HDI (2011)" = '0.453 (low)';

Question: What is the population in millions for 2011 where the GDP (nominal) (billions USD) is 4? 
SQL: SELECT "Population (millions, 2011)" FROM "1-2155836-1" WHERE "GDP (nominal) (billions USD)" = '4';

Question: What is the HDI for 2011 in Tunisia? 
SQL: SELECT "HDI (2011)" FROM "1-2155836-1" WHERE "Country" = 'Tunisia';

Question: What is the area (km2) where the population in millions for 2011 is 37.1? 
SQL: SELECT "Area (km²)" FROM "1-2155836-1" WHERE "Population (millions, 2011)" = '37.1';

Question: What is the GDP (PPP) (USD, per capita) for Algeria? 
SQL: SELECT MIN("GDP (PPP) (USD, per capita)") FROM "1-2155836-1" WHERE "Country" = 'Algeria';

Question: What is the GDP (nominal) (billions USD) where the population in millions for 2011 is 3.4? 
SQL: SELECT "GDP (nominal) (billions USD)" FROM "1-2155836-1" WHERE "Population (millions, 2011)" = '3.4';