Please solve this question

[E An air capacitor is made by using two flat plates, each with area A, separated by a distance d. Then a metal slab having thickness 3 (less than d) and the same shape and size as the plates is inserted between them, parallel to the plates and not touching either plate. When the metal slab is not present, what is the capacitance of this arrangement, C0? 0 Co = 60A/cl O 00 = 47reoAd O 00 = 41reoA/d O 00 = EOA/d O 00 = A/41rsoAd [I]