As shown in the diagram,$\overline{ OA }$ and $\overline{ OB }$ are two radii of $\odot( O , 21 \text{ cm} )$ perpendicular to each other. If $OD = 10 \text{ cm}$,find the area of the shaded region. (in $\text{cm}^2$)

Area of the largest triangle that can be inscribed in a semi-circle of radius $r$ units is

Find the area of the minor segment of a circle of radius $14 \, cm$,when the angle of the corresponding sector is $60^{\circ}$. (in $cm^{2}$)

Find the area of the shaded region in the figure where arcs drawn with centers $A, B, C,$ and $D$ intersect in pairs at mid-points $P, Q, R,$ and $S$ of the sides $AB, BC, CD,$ and $DA,$ respectively of a square $ABCD$ (Use $\pi = 3.14$) (in $cm^{2}$).

In the figure,$ABCD$ is a trapezium with $AB \parallel DC$,$AB = 18 \, cm$,$DC = 32 \, cm$,and the distance between $AB$ and $DC = 14 \, cm$. If arcs of equal radii $7 \, cm$ with centers $A, B, C$,and $D$ have been drawn,find the area of the shaded region of the figure (in $cm^2$).

$A$ cow is tied with a rope of length $14 \, m$ at the corner of a rectangular field of dimensions $20 \, m \times 16 \, m$. Find the area of the field in which the cow can graze. (in $m^2$)