\[\boxed{\ \mathbf{997\ (997)}.\ Еуроки\ - \ ДЗ\ без\ мороки}\]
\[P = 12,8\ см\]
\[a = P\ :4 = 12,8\ :4 =\]
\[= 3,2\ (см) - сторона.\]
\[S = a^{2} = {3,2}^{2} = 3,2 \cdot 3,2 =\]
\[= 10,24\ \left( см^{2} \right) - площадь\ \]
\[квадрата.\]
\[Ответ:10,24\ см^{2}.\]
\[\boxed{\mathbf{997}\mathbf{.}\mathbf{\ }}\]
\[1)\ \frac{12}{23} < \frac{x}{23} < 1\ \ \]
\[x = 13,\ 14,\ 15,\ 16,\ 17,\ 18,\ 19,\ 20,\ \]
\[21,\ 22.\]
\[2)\ \frac{4}{9} < \frac{x}{36} < \frac{11}{12}\text{\ \ \ }\]
\[\frac{16}{36} < \frac{x}{36} < \frac{33}{36}\text{\ \ \ }\]
\[x = 17,\ 18,\ 19,\ 20,\ 21,\ 22,\ 23,\ 24,\ \]
\[25,\ 26,\ 27,\ 28,\ 29,\ 30,\ 31,\ 32.\]