The ratio between the areas of two circles is $4: 7.$ What will be the ratio of their radii?

The area of a parallelogram is $72 \, cm^{2}$ and its altitude is twice the corresponding base. The length of the base is.....$cm$.

What is the area of a given right-angled triangle?
$I.$ The length of the hypotenuse is $5\, cm$.
$II.$ The perimeter of the triangle is four times that of its base.
$III.$ One of the angles of the triangle is $60^{\circ}$.

The radius and vertical height of a cone are $5 \text{ cm}$ and $12 \text{ cm}$ respectively. Then its lateral surface area is? (in $\text{cm}^2$)

In the given figure,$y$ is both the radius of the larger circle and the diameter of the smaller circle. Find the area of the shaded region.

$A$ ladder is resting with one end in contact with the top of a wall of height $12\, m$ and the other end on the ground is at a distance $5\, m$ from the wall. The length of the ladder is.....$m$