2. (30 pts.) A long metal pipe of circular cross-section and radius R is divided into four equal sections (see the picture below). Three of them are at constant potential V and the forth section is grounded. Use cylindrical coordinates to find V=V a) Electric potential inside of the pipe, b) Electric potential outside of the pipe, c) Electric field inside of the pipe, d) Electric field outside of the pipe, e) Surface density of electric charge on the inner and on the outer surfaces of the pipe