CREATE TABLE table_21160 ("Municipality" TEXT, "Income Class" TEXT, "District" TEXT, "Population  ( 2010 ) " FLOAT, "Area  ( km\\u00b2 ) " FLOAT)

what is the income class for area 75?
SELECT "Income Class" FROM table_21160 WHERE "Area (km\u00b2)" = '75'
SELECT "Income Class" FROM "table_21160" WHERE "Area (km\u00b2)" = '75'