A certain substance has a dielectric constant of 2.8 and a dielectric strength of 18.0 MV/m. If it is used as the dielectric material in a parallel-plate capacitor, what minimum area should the plates of the capacitor have to obtain a capacitance of 9.00×10-8 F and to ensure that the capacitor will be able to withstand a potential difference of 4.5 kV?