A charged oil drop that has a mass of 5.40 x 10^-12 kg and carries 10 elementary charges is centered 50 mm below the center of an oppositely charged sphere that has a radius of 5.0 mm. Treat the drop as a particle. Part A What charge must the sphere be given therefore that the electric force it exerts on te drop causes the drop to float in the air for an instant? Express your answer to two important digits and include the appropriate units. q = Value Units