50. A cloud layer is 1000 m above the planet, with the area of 1x106 m2, considered as the plates of a parallel-plate capacitor. If anelectric field strength is greater than 3.0x106 N/C, it causes lightning, what is the maximum charge the cloud can hold?(εo= 8.85 x 10-12 C2/N•m2)
(A) 28.55 C
(B) 26.55 C
(C) 24.55 C
(D) 22.55 C
(E) 20.55 C