A capacitor of capacitance C1 is charged to a potential V1 while another capacitor of          
      capacitance C2 is charged to a potential difference V2 The capacitors are now disconnected   
      from their respective charging batteries and connected in parallel to each other. (a) Find the  
       total energy stored in the two capacitors before they are connected.
      (b) Find the total energy stored in the parallel combination of the two capacitors.
      (c) Explain the reason for the difference of energy in parallel combination in comparison to    
        the total energy before they are connected.