A capacitor has capacitance 5 $$\mu$$F when its parallel plates are separated by air medium of thickness $$d$$. A slab of material of dielectric constant 1.5 having area equal to that of plates but thickness $$\frac{d}{2}$$ is inserted between the plates. Capacitance of the capacitor in the presence of slab will be _____ $$\mu$$F.