4.0 μF. 4.0 μF 10.0 μF 7.0 µF 4.0 μΕ| 7.0 µF 5.0 µF b а 6.0 μF 6.0 μF

For the circuit in Figure 1:

a) . Determine the equivalent capacitance of the system.

b) If the potential difference between point a and b is 100 V, determine the energy 10 μF capacitor stored.

c)  If all the capacitors initially had air and now they have been put as material graphite dielectric (k = 12.5), what is the difference in charge of the 6 μF capacitor near point b?