\[\boxed{\text{548\ (548).}\text{\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[\textbf{а)}\ \left( - x^{3} \right)^{7} = - x^{21}\]
\[\textbf{б)}\ \left( - x^{2} \right)^{5} = - x^{10}\]
\[\textbf{в)}\ ( - x)^{4} \cdot x^{8} = x^{4} \cdot x^{8} = x^{4 + 8} =\]
\[= x^{12}\]
\[\textbf{г)}\ \left( - x^{5} \right)^{7} \cdot \left( x^{2} \right)^{3} = - x^{35} \cdot x^{6} =\]
\[= - x^{35 + 6} = - x^{41}\]