CREATE TABLE table_203_749 (id DECIMAL, "call sign" TEXT, "frequency" TEXT, "city of license" TEXT, "licensee" TEXT, "format" TEXT)

what call sign is listed directly before kbmk ?
SELECT "call sign" FROM table_203_749 WHERE id = (SELECT id FROM table_203_749 WHERE "call sign" = 'kbmk') - 1
SELECT "call sign" FROM "table_203_749" WHERE "id" = (SELECT "id" FROM "table_203_749" WHERE "call sign" = 'kbmk') - 1