\text { Evaluate } \int_{-2}^{0} \int_{-\sqrt{4-x^{2}}}^{\sqrt{4-x^{2}}} \int_{0}^{\sqrt{4-x^{2}-y^{2}}} \frac{2 x}{\sqrt{x^{2}+y^{2}+z^{2}}} d z d y d x

Fig: 1