The radius of a circle is $12 \, cm$. Find its circumference and area $(\pi = 3.14)$.

The diagram below is formed by three semicircles. If $OA = OB = 70\, cm,$ find the area of the figure formed (in $cm^2$).

The radius of a circle whose circumference is equal to the sum of the circumferences of the two circles of diameters $36 \, cm$ and $20 \, cm$ is (in $cm$)

Sides of a triangular field are $15 \, m$,$16 \, m$,and $17 \, m$. At the three corners of the field,a cow,a buffalo,and a horse are tied separately with ropes of length $7 \, m$ each to graze in the field. Find the area of the field which cannot be grazed by the three animals.

Find the area of the shaded field shown in the figure.

The floor of a room has dimensions $5 \, m \times 4 \, m$ and it is covered with circular tiles of diameter $50 \, cm$ each,as shown in the figure. Find the area of the floor that remains uncovered by the tiles. (Use $\pi = 3.14$) (in $m^2$)