Two charges are set on the x-axis 9.50 cm away from each other. The charges are 17.4 nC and -6.40 nC. Calculate the electric field at the point on the x-axis between the charges where the electric potential is zero.
a) 41.7 N/C
b) -41.7 N/C
c) 20.85 N/C
d) -20.85 N/C