A Van De Graaff Generator Has a Spherical Dome of Radius

A Van de Graaff generator has a spherical dome of radius 27 cm.Operating in dry air,where "atmospheric breakdown" is at E_max = 3.0 × 10⁶ N/C,what is the maximum charge that can be held on the dome? (k_e = 8.99 × 10⁹ N⋅m²/C²)
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A) 4.9 × 10−⁵ C
B) 2.4 × 10−⁵ C
C) 1.2 × 10−⁶ C
D) 24.3 × 10−⁶ C
E) ​0.9 × 10−⁶ C