\[\left( - 0,1x^{3} \right)^{4} \cdot 10x =\]
\[= \left( - \frac{1}{10} \right)^{4}x^{12} \cdot 10x =\]
\[= \frac{1}{10^{3}}x^{13} = 0,001x^{13}.\]