A power source supplies an electric potential difference of 9.0 V to the plates of a capacitor. The energy stored in the capacitor is 9.8 × 10–4 J. The dielectric constant of the dielectric in the capacitor is 5.1. The ratio of the area of the plates to the distance between the plates, rounded to two significant figures, is
× 10^5 m.

Quizlet says 5.4 as the answer. Not sure if that's right.