複選題

4. Suppose a point charge q is held a distance d above an infinite grounded conducting plane. Given that the conducting plane is the x-y plane and the point charge q is at (0, 0, d).
(A) The potential on the conducting plane is constant.
(B) The potential far away from the charge is 0.
(C) An image charge q can be set at (0, 0, -d) to remove the conducting plane while still satisfying the same boundary conditions.
(D) The induced charge on the conducting plane is O
(E) The induced charge on the conducting plane is