The ratio of the areas of $\odot(O, 6)$ and $\odot(P, 12)$ is ...........

In a circle with radius $7 \, cm$,the perimeter of a minor sector is $\frac{86}{3} \, cm$. Then,the area of that minor sector is $\ldots \ldots \ldots \ldots cm^2$.

Which of the following correctly matches the information given in Part $I$ and Part $II$?

Part $I$	Part $II$
$1.$ Formula to find the length of a minor arc	$a.$ $C=2\pi r$
$2.$ Formula to find the area of a minor sector	$b.$ $A=\pi r^{2}$
$3.$ Formula to find the area of a circle	$c.$ $l=\frac{\pi r \theta}{180}$
$4.$ Formula to find the circumference of a circle	$d.$ $A=\frac{\pi r^{2} \theta}{360}$

The area of a circular playground is $22176 \, m^{2}$. Find the cost of fencing this ground at the rate of $Rs. \, 50$ per $metre$. (in $Rs.$)

Three circles each of radius $3.5\, cm$ are drawn in such a way that each of them touches the other two. Find the area enclosed between these circles. (in $cm^{2}$)

The ratio of the radii of two circles is $4: 5$. Then,the ratio of their areas is...........