Which of the following combination of 7 identical capacitors each of $$2 \mu \mathrm{F}$$ gives a capacitance of $$\frac{10}{11} \mu \mathrm{F}$$ ?

In a parallel plate capacitor with air between the plates, the distance $$d$$ between the plates is changed and the space is filled with dielectric constant 8. The capacity of the capacitor is increased 16 times, the distance between the plates is

In the given figure, the equivalent capacitance between points A and B is

If the charge on the capacitor is increased by 3 coulombs, the energy stored in it increases by $$44 \%$$. The original charge on the capacitor is