An Ideal Air-Filled Parallel-Plate Capacitor Consists of Two Circular Plates $0.30 \mathrm {~mm}$

An ideal air-filled parallel-plate capacitor consists of two circular plates, each of radius $0.30 \mathrm {~mm}$ . How far apart should the plates be for the capacitance to be $300.0 - \mathrm { pF } ? \left( \varepsilon _ { 0 } = 8.85 \times 10 ^ { - 12 } \right.$ $\mathrm { C } ^ { 2 } / \mathrm { N } \cdot \mathrm { m } ^ { 2 }$ )

A) $0.0042 \mu \mathrm { m }$
B) $0.0083 \mu \mathrm { m }$
C) $0.00094 \mu \mathrm { m }$
D) $0.00047 \mu \mathrm { m }$