A positive charge +q1 is located to the left of a negative charge -q2. On a line passing through the two charges, there are two places where the total potential is zero. The first place is betwween the charges and is 4 cm to the left of the negative charge. The second place is 7 cm to the right of the negative charge.
(a) What is the distance between the charges?
(b) Find q1/q2, the ratio of the magnitudes of the charges.