In the figure,a square $OABC$ is inscribed in a quadrant $OPBQ$. If $OA = 20 \, cm,$ find the area of the shaded region. (in $cm^2$) (Use $\pi = 3.14$)

In the figure,$AB$ and $CD$ are two diameters of a circle (with centre $O$) perpendicular to each other. $OD$ is the diameter of the smaller circle. If $OA = 7 \, cm$,find the area of the shaded region in $cm^2$. [Use $\pi = \frac{22}{7}$]

Calculate the area of the designed region in the figure,which is common between the two quadrants of circles of radius $8 \, cm$ each. $\left[\text{Use } \pi = \frac{22}{7}\right]$

In the given figure,$OACB$ is a quadrant of a circle with centre $O$ and radius $3.5 \, cm$. If $OD = 2 \, cm$,find the area of the:
$(i)$ quadrant $OACB$,
$(ii)$ shaded region. $\left[ \text{Use } \pi = \frac{22}{7} \right]$

$A$ chord of a circle of radius $10\, cm$ subtends a right angle at the centre. Find the area of the corresponding:
$(i)$ minor segment $\&$ $(ii)$ major sector. (Use $\pi=3.14$ )

The figure depicts a racing track whose left and right ends are semicircular.
The distance between the two inner parallel line segments is $60 \, m$ and they are each $106 \, m$ long. If the track is $10 \, m$ wide,find:
$(i)$ the distance around the track along its inner edge
$(ii)$ the area of the track. $\left[ \text{Use } \pi = \frac{22}{7} \right]$