Two point charges, 4.0 µC and -2.0 µC, are placed 5.4 cm apart on the x axis, such that the -2.0 µC charge is at x = 0 and the 4.0 µC charge is at x = 5.4 cm.

(a) At what point(s) along the x axis is the electric field zero? (If there is no point where E = 0 in a region, enter "0" in that box.)
x < 0 cm
(b) At what point(s) along the x axis is the potential zero? Let V = 0 at r = . (If there is no point where V = 0 in a region, enter "0" in that box.)
x < 0 cm
0 < x < 5.4 cm cm