Question: List the object classes of image ID 36 with coordinates (0,0).
SQL: SELECT T2.OBJ_CLASS FROM IMG_OBJ AS T1 INNER JOIN OBJ_CLASSES AS T2 ON T1.OBJ_CLASS_ID = T2.OBJ_CLASS_ID WHERE T1.IMG_ID = 36 AND T1.X = 0 AND T1.Y = 0