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 ï40 c at height 1 000 m, what is the magnitude of the electric field e at the aircraft? (ke = 8.99 ï´ 109 n·m2/c2)