???? ???? ??????? ?? ?????? ?????? ???? ???? ??? ??????? ?? ???? ??? ??????? ??????? . ????? ??? ??????? ??????? ???? ??????? ??? ???????. ????? ??????? ??????? ?????????. ????? ?????? ?????? ?????? ???????? ???????. ???? ??????? ??????? ????? ????? ?? ???????. ?????? ???? ????? ??????? ??? seeking ???? ?????? need to ????? ??? factors.