In the adjoining diagram, $\overline{ AB }$ and $\overline{ CD }$ are diameters of $\odot( O , 7\, cm )$ perpendicular to each other. A circle is drawn with diameter $\overline{ OD }$. Find the area of the shaded region. (in $cm^2$)
As shown in the diagram, $\triangle ABC$ is an equilateral triangle in which $BC =70 \,cm$ and $P$ and $R$ are midpoints of $\overline{ AB }$ and $\overline{ AC }$ respectively. $\widehat{ PQR }$ is an arc of $\odot( A , AP ) .$ Find the area of the shaded region. $(\sqrt{3}=1.73)$ (in $cm^2$)
As shown in the diagram, $\overline{ OA }$ and $\overline{ OB }$ are two radii of $\odot( O , 21 cm )$ perpendicular to each other. If $OD =10 \,cm ,$ find the area of the shaded region. (in $cm^2$)
Area of a sector of a circle of radius $36\, cm$ is $54 \pi \,cm ^{2}$. Find the length of the corresponding arc of the sector. (in $cm$)
In the adjotning flgure, $PS$ is diemeter of a circle and $PS$ $=12$. $P Q=Q R=R S$ Semicircles are drawn with dinmeter $\overline{\text { PQ }}$ and $\overline{QS}$. Find the perimeter and the area Find the perimeter and the arce of the shaded region. $(\pi=3.14)$