A Parallel-Plate Air-Filled Capacitor Is Made from Two Plates That $0.070 \mathrm {~m}$

A parallel-plate air-filled capacitor is made from two plates that are $0.070 \mathrm {~m}$ on each side and spaced $9.2 \mathrm {~mm}$ apart. What must the potential difference between the plates be to produce an energy density of $0.062 \mathrm {~J} / \mathrm { m } 3$ in the region between them? $\left( \varepsilon _ { 0 } = 8.85 \times 10 ^ { - 12 } \right.$ $\left. \mathrm { C } ^ { 2 } / \mathrm { N } \cdot \mathrm { m } ^ { 2 } \right)$