CREATE TABLE table_37015 ("School" TEXT, "Location" TEXT, "Mascot" TEXT, "County" TEXT, "Enrollment 08-09" FLOAT, "IHSAA Class" TEXT, "IHSAA Class Football" TEXT, "Year Joined" FLOAT, "Previous Conference" TEXT)

In what county is the school of Merrillville?
SELECT "County" FROM table_37015 WHERE "School" = 'merrillville'
SELECT "County" FROM "table_37015" WHERE "School" = 'merrillville'