\[\left( \frac{1}{10}\text{xyz} \right)^{4} = \left( \frac{1}{10} \right)^{4}x^{4}y^{4}z^{4} =\]
\[= \frac{1}{10000}x^{4}y^{4}z^{4} = 0,0001x^{4}y^{4}z^{4}.\]