A large copper sheet of thickness l is inserted between the plates of a parallel-plate capacitor. (The distance between each plate and the sheet is (d' - l)/2, where d' is the distance between the plates.) Is the capacitance affected by the copper sheet (a conductor, not a dielectric)? If so, what is the new capacitance? If not, why not? (Recall that the capacitance of a parallel- plate capacitor is given by eDA=d, where eD is the permittivity of free space, A is the area of each plate, and d is the separation between the plates.)