In the figure below, the capacitance of each capacitor is $$3 \mu \mathrm{F}$$. The effective capacitance between $$A$$ and $$B$$ is

If $$C$$ be the capacitance and $$V$$ be the electric potential, then the dimensional formula of $$\mathrm{CV}^2$$ is

In the figure, first the capacitors are fully charged by closing the key $$\mathrm{K}$$. Then after opening the Key a dielectric material with dielectric constant 2 is filled in the space between the plates of both the capacitor. At this state the ratio of the Charge on the capacitor $$C_1$$ to that of $$C_2$$ is:

If R and C denote resistance and capacitance of a material, then the dimension of CR will be :