i.4.33 Curvilinear integrals

Condition: Calculate the curvilinear integral of the 1st kind, taken along spatial curves: \[ \int_{C} x^{2} d s \text {, where } C-\text { circle } x^{2}+y^{2}+z^{2}=a^{2} \text {, } \] \[ x+y+z=0 \]