CREATE TABLE table_73907 ("Municipality" CLOB, "No. of Barangays" FLOAT, "Area  ( km\\u00b2 ) " CLOB, "Population  ( 2010 ) " FLOAT, "Pop. density  ( per km\\u00b2 ) " CLOB, "Income Class  ( 2004 ) " CLOB)

List the population density per kilometer for the city of abra de ilog.
SELECT "Pop. density (per km\u00b2)" FROM table_73907 WHERE "Municipality" = 'Abra de Ilog'
SELECT "Pop. density (per km\u00b2)" FROM "table_73907" WHERE "Municipality" = 'Abra de Ilog'