Hello, may I get a step-by-step explanation for each? Thank you!

Two equipotential surfaces surround a + 1.90 x 10--C point charge. How far is the 190-V surface from the 50.0-V surface? Number UnitsTwo identical capacitors store different amounts of energy: capacitor A stores 4.0 x 10" J, and capacitor B stores 1.5 x 10-4J. The voltage across the plates of capacitor B is 12 V. Find the voltage across the plates of capacitor A. Number i UnitsTwo hollow metal spheres are concentric with each other. The inner sphere has a radius of 0.138 m and a potential of 87.9 V. The radius of the outer sphere is 0.151 m and its potential is 71.5 V. If the region between the spheres is filled with Teflon, find the electric energy contained in this space. Number i Units