In $\odot (P, 20)$,the area of a minor sector is $150\, cm^2$. The length of the arc corresponding to that sector is $\dots\, cm$.

The perimeter of a semicircular table-top is $3.60 \, m$. Then,its radius is $\ldots \ldots \ldots \, cm$.

In the figure, a circle of radius $7.5 \, cm$ is inscribed in a square. Find the area of the shaded region (Use $\pi = 3.14$) (in $cm^2$).

As shown in the diagram,rectangle $ABCD$ is inscribed in a circle. If $AB = 8 \, cm$ and $BC = 6 \, cm$,find the area of the shaded region in the diagram. $(\pi = 3.14)$ (in $cm^2$)

The length of the minute hand of a clock is $6 \, cm$. The area of the region swept by it in $10 \, \text{minutes}$ is $\ldots \ldots \ldots \ldots \, cm^2$. $(\pi = 3.14)$

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 ........