The fig ure show s two concentric thin spherical shells Sphere-A of radius RA= 20 cm and a total charge QA+15 nC. What is the net electric flux through the

spherical surface of radius r= 23 cm encompassing the two charges QA and Qs? What is the magnitude of the electric field at r= 17.5 cm from the center of the spheres? What is the magnitude of the electric field at r= 10 cm from the center of the spheres? Sphere-B of radius RB= 15 cm anda total charge Qe =-25 nC.