?? ?? ?????? ????? ?? ????? ??????????? {???????????? ???? ??? ??? ?? ?? ?????? ?????? ?? ?? ???? ????? ?? ??? ?? ????? ???? ?? ???? ??? CHAIR FOR REPAIRING ????? ????? ???? AN ESSENTIAL TOOL ???? ?? ??? ?? IS INVOLVED IN REPAIR WORKS. ????? ????? ???? ?? ?????? ???? ????? ? ?? ????? ??? ????? ?? GIVES ?? IN DIFFERENT POSITIONS ?? ????? ??? ???