Let C₁ and C₂ be the centres of the circles ${\mathrm{x}}^2+{\mathrm{y}}^2-2\mathrm{x}-2\mathrm{y}-2=0$ and ${\mathrm{x}}^2+{\mathrm{y}}^2-6\mathrm{x}-6\mathrm{y}+14=0$ respectively. If P and Q are the points of intersection of these circles then, the area (in sq units) of the quadrilateral PC₁ QC₂ is