?? ??? ???? ????? ??? ?????? ????? ??? ?? ??? ??? ??????? ????? ???? ???? ??? ?? ??? ?? ??? ???? ???? ?????? ???? ?? ???? ?????? ????? ????? ? ??? ???????? ????? ??????? ?????? -- ??? ?? ??? -- ??? ??????? ???? ?????? ????? ????? ??? ???? ??? ??????? ??? 2 π {\displaystyle 2\pi \,} ???
C i r c u m f e r e n c e = 2 π r {\displaystyle Circumference=2\pi r\,}
A r e a = π r 2 {\displaystyle Area=\pi r^{2}\,}