If the perimeter of a circle is equal to that of a square,then the ratio of their areas is

Points $A$ and $B$ are distinct points on $\odot(O, r)$ and point $C$ on the circle lies in the interior of $\angle AOB$. Then,$\overline{AB} \cup \widehat{ACB}$ is ........

The ratio of radii of two circles is $2:3$ and the ratio of the angles at the centre of two minor sectors of those circles is $5:2$. Then,the ratio of the areas of those sectors is:

The area of a circle is $3850 \, cm^2$. In that circle,the length of an arc subtending a right angle at the centre is $\ldots \ldots \ldots \, cm$.

The radius of a circular ground is $56\,m$. $A$ $7\,m$ wide road runs around its boundary inside the ground. Some region of the road as shown by the shaded part in the diagram is to be repaired. Find the cost of repairing at the rate of ₹ $40/m^2$ (in ₹).

The area of $\odot(O, r)$ is $240 \, cm^2$. In $\odot(O, r)$,minor arc $\widehat{ACB}$ subtends an angle of measure $45^\circ$ at the centre. Then,the area of minor sector $OACB$ is $\dots \dots \dots \, cm^2$.