In a velocity selector, a uniform magnetic field of around 1.5 T from a big magnet and two parallel plates having a separation distance of 1.5 cm generate a perpendicular electric field. Determine what voltage must be exerted across the plates so that (i) a singly charged ion traveling at the speed of 8.0 x 104 m/s will pass via undeflected or (ii) a doubly charged ion traveling at the similar speed will pass via undeflected?