A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is
(A) 28.2 mm (B) 26.4 mm
(C) 24.4 mm (D) 22.0 mm
(A) 28.2 mm (B) 26.4 mm
(C) 24.4 mm (D) 22.0 mm