An ion with charge of Q = +3.2 x 10-19 C is in a region where a uniform electric field of magnitude E = 5.0 X 105 V/m is perpendicular to a uniform magnetic field B = 0.80 T. If the ion's acceleration is zero then what is its speed v? a) v = 1.6 x 10-5 m/s b) v = 4.0 x 105 m/s c) v = 6.3 x 105 m/s d) v = 0 m/s