In a particular region of the earth's atmosphere, the electric field above the earth's surface has been measured to be 149 N/C downward at an

In a particular region of the earth's atmosphere, the electric field above the earth's surface has been measured to be 149 N/C downward at an altitude of 252 m and 168 N/C downward at an altitude of 405 m. Calculate the volume charge density of the atmosphere assuming it to be uniform between 252 and 405 m. Neglect the curvature of the earth.