\[\boxed{\mathbf{873\ (873)}\mathbf{.}\mathbf{\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[\textbf{а)}\]
\[O(0)\]
\[B\left( - 1\frac{1}{3} \right);\ \ \ B_{1}\left( 1\frac{1}{3} \right)\]
\[C\left( - \frac{2}{3} \right);\ \ C_{1}\left( \frac{2}{3} \right)\]
\[D\left( 1\frac{2}{3} \right);\ \ D\left( - 1\frac{2}{3} \right)\]
\[E(1);\ \ \ E_{1}( - 1).\]
\[\textbf{б)}\ \]
\[O(0)\]
\[A(0,3);\ \ A_{1}( - 0,3)\]
\[B(0,9);\ \ B_{1}( - 0,9)\]
\[N( - 0,5);\ \ N_{1}(0,5)\]
\[M( - 1);\ \ M_{1}(1).\]