Find the area of the shaded region in the figure if $ABCD$ is a square of side $14 \, cm$ and $APD$ and $BPC$ are semicircles. (in $cm^2$) [Use $\pi = \frac{22}{7}$]

Find the area of the shaded region in the figure,if the radii of the two concentric circles with center $O$ are $7\, cm$ and $14\, cm$ respectively and $\angle AOC = 40^{\circ}$. [Use $\pi = \frac{22}{7}$]

Find the area of the sector of a circle with radius $4\, cm$ and of angle $30^{\circ}$. Also,find the area of the corresponding major sector (in $cm^2$) (Use $\pi = 3.14$).

From each corner of a square of side $4\, cm$,a quadrant of a circle of radius $1\, cm$ is cut and also a circle of diameter $2\, cm$ is cut as shown in the figure. Find the area of the remaining portion of the square. [Use $\pi = \frac{22}{7}$]

Find the area of a quadrant of a circle whose circumference is $22 \, cm$. [use $\pi = \frac{22}{7}$]

$AB$ and $CD$ are respectively arcs of two concentric circles of radii $21\, cm$ and $7\, cm$ with centre $O$ (see figure). If $\angle AOB = 30^{\circ}$,find the area of the shaded region.