\[\boxed{\text{268\ (}\text{н}\text{).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[1)\ \frac{7}{16}a^{2}b^{4}\ \]
\[если\ a = - \frac{1}{7};\ \ \ b = 2:\]
\[\frac{7}{16} \cdot \left( - \frac{1}{7} \right)^{2} \cdot 2^{4} = \frac{7}{16} \cdot \frac{1}{49} \cdot 16 =\]
\[= \frac{7}{49} = \frac{1}{7}.\]
\[2)\ 0,8m^{2}n^{2}k\text{\ \ }\]
\[если\ m = 0,3;\ \ n = \frac{1}{2};\ \ \ k =\]
\[= 2000:\]
\[0,8 \cdot {0,3}^{2} \cdot \left( \frac{1}{2} \right)^{2} \cdot 2000 =\]
\[= 0,8 \cdot 0,09 \cdot \frac{1}{4} \cdot 2000 = 36.\]
\[\boxed{\text{268\ (}\text{с}\text{).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[1)\ 3m^{3}\]
\[если\ m = - 3:\]
\[3 \cdot ( - 3)^{3} = - 3 \cdot 27 = - 81.\]
\[2)\ \frac{7}{16}a^{2}b^{4}\]
\[если\ a = - \frac{1}{7};\ \ \ b = 2:\]
\[\frac{7}{16} \cdot \left( - \frac{1}{7} \right)^{2} \cdot 2^{4} = \frac{7}{16} \cdot \frac{1}{49} \cdot 16 =\]
\[= \frac{7}{49} = \frac{1}{7}.\]
\[3)\ 0,8m^{2}n^{2}k\]
\[если\ m = 0,3;\ \ n = \frac{1}{2};\ \ \ k =\]
\[= 2000:\]
\[0,8 \cdot {0,3}^{2} \cdot \left( \frac{1}{2} \right)^{2} \cdot 2000 =\]
\[= 0,8 \cdot 0,09 \cdot \frac{1}{4} \cdot 2000 = 36.\]