Question: What is the highest Population per km² (2009) that is in western province, with an Area (km²) larger than 5475?
SQL: SELECT MAX("Population per km² (2009)") FROM "2-1604559-1" WHERE "Province" = 'western province' AND "Area (km²)" > 5475.0;

Question: What is the lowest Population per km² (2009) that has a solomon islands province, with an Area (km²) smaller than 28400?
SQL: SELECT MIN("Population per km² (2009)") FROM "2-1604559-1" WHERE "Province" = 'solomon islands' AND "Area (km²)" < 28400.0;

Question: What is the lowest population census from 1999 with an Area (km²) of 4225, and a Population per km² (2009) fewer than 32.6?
SQL: SELECT MIN("Population census 1999") FROM "2-1604559-1" WHERE "Area (km²)" = 4225.0 AND "Population per km² (2009)" < 32.6;