i.4.44 Curvilinear integrals

condition: Find the mass of the arc of a homogeneous spatial curve: \[ y=a \cdot \sin ^{-1} \frac{x}{a}, \quad z=\frac{a}{4} \ln \frac{a-x}{a+x} \] from the point \( O(0 ; 0 ; 0) \) to the point \( A\left(\frac{a \pi}{6}, \frac{a}{4} \ln \frac{1}{3}, \frac{a}{2}\right) \).