Three identical metal plates with large surface areas are kept para...

Three identical metal plates with large surface areas are kept parallel to each other as shown in figure. The leftmost plate is given a charge \( Q \), the rightmost a charge \( -2 Q \) and the middle one remains neutral. Find the charge appearing on the outer surface of the rightmost plate:
(1) \( -Q / 4 \)
(2) \( -2 Q \)
(3) \( -Q \)
(4) \( -Q / 2 \)