A particle of charge 2.0×10-8 C experiences an upward force of magnitude 4.0×10-6 N when it is placed in a particular point in an electric field. What is the electric field at that point? 4.0×10^2 N/C up 2.0×10^2 N/C up 4.0×10^2 N/C down 2.0×10^2 N/C down