???? ???? ??????? ?? ?????? ?????? ???? ???? ??? ??????? ?? ???? ??? ??????. ????? ??? ??????? ??????? ???? ?????? ??? ??????. ????? ??????? ??????? ?????????. ????? ?????? ?????? ?????? ??????. ???? ??????? ??????? ????? ???? ?? ???????? . Picking ???? ????? ??????? ??? seeking ???? ?????? need to consider ??? factors. , First and for