Circle $C_1$ passes through the centre of the circle $C_2$ and is tangential to it. If the area of $C_1$ is $4 {\mathrm{cm}}^2$ then the area of $C_2$ is _ .

In the given figure $AP=3 \mathrm{cm}$, the area of the shaded region is _____.

An oval shaped meeting table made of wood has its dimension as shown in figure. Find the cost of polishing it at $₹3.50 \mathrm{per} \mathrm{sq}.\mathrm{m}$. (use $\mathrm{\pi }=3.14$)

In the given figure three circles of radius 2cm touch one another externally. These circles are circumscribed by a circle of radius $R \mathrm{cm}$, Find the area $(\mathrm{in} {\mathrm{cm}}^2)$ of the shaded region in terms of $\mathrm{\pi }$ and $\surd 3$).