Two capacitors have a total capacitance of 25 μF when connected in parallel and 6 μF when connected in series. What are their individual capacitances?

If three capacitors, each of capacitance 12 μF, are connected in parallel, what is the total equivalent capacitance?

A parallel plate capacitor is charged by a battery, and the battery remains connected. A dielectric slab of dielectric constant 'K' is inserted between the plates and then taken out. The final electric field between the plates, compared to its initial value before insertion, will: