Two circles, both of radii $1$ cm, intersect such that the circumference of each one passes through the centre of the other. What is the area (in sq cm) of the intersecting region?
- $\frac{\pi}{3} - \frac{\sqrt{3}} {4} $
- $\frac{2 \pi}{3} + \frac{\sqrt{3}} {2} $
- $\frac{4 \pi}{3} - \frac{\sqrt{3}} {2} $
- $\frac{4 \pi}{3} + \frac{\sqrt{3}} {2} $
- $\frac{2 \pi}{3} - \frac{\sqrt{3}} {2} $