需要通过验证才能下载！希望大家多多合作！否则不能下载！请谅解！

				% 6-4-1.ty
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				write(-0.5,-0.5)[rt]{$O$},
				write(39,-1)[t]{$A$},
				write(11,21)[b]{$B$},
				write(50,21)[b]{$C$}}}
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				\vspace{1cm}
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				write(39,-1)[t]{$A$},
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				write(50,21)[b]{$C$}}}
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				\end{center}
				\end{document}