A spherical capacitor consists of two concentric spherical conductors, held in position by suitable insulating supports (Fig. 2.34). Show that the capacitance of a spherical capacitor is given by
`C = (4 pi epsilon_(0)r_(1)r_(0))/(r_(1)-r_(2))`

where `r_(1)` and `r_(2)` are the radii of outer and inner spheres, respectively.