Step-by-step explanation:
Given that,
Electric field = 6500 N/C
Charge

Distance = 6.00 cm
(a). When a charge is moved in the positive x direction
We need to calculate the electric potential energy
Using formula of potential energy



Put the value into the formula


The change in electric potential energy is
.
(b). When a charge is moved in the negative x direction
We need to calculate the electric potential energy
Using formula of potential energy

Put the value into the formula


The change in electric potential energy is
.
(c). When a charge is moved in the positive y direction
We need to calculate the electric potential energy
Using formula of potential energy


Because the electric field direction is perpendicular to the movement.
So, The change in electric potential energy is zero.
Hence, This is the required solution.