An Airplane Is Flying Through a Thundercloud at a Height

An airplane is flying through a thundercloud at a height of 2 000 m.(This is a very dangerous thing to do because of updrafts,turbulence,and the possibility of electric discharge. ) If there is a charge concentration of +40 C at height 3 000 m within the cloud and -40 C at height 1 000 m,what is the magnitude of the electric field E at the aircraft? (k_e = 8.99 x 10⁹ N·m²/C²)

A) 90 000 N/C
B) 180 000 N/C
C) 360 000 N/C
D) 720 000 N/C