Electrostatic Potential and Capacitance Part 2

A parallel plate capacitor with plate area A and plate separation d is filed with a dielectric material of dielectric constant K=4. The thickness of the dielectric material is x, where x<d.
Let C1 and C2 be the capacitance of the system for x=‌

1

3

d and x=‌

2d

3

, respectively. If C1=2µF the value of C2 is _________ µF