The area of the base of a cylinder is $616\,cm^{2}$. Then,the radius of the base of the cylinder is $\ldots \ldots \ldots \ldots cm.$

The base of a cone with radius $21 \, cm$ and height $20 \, cm$ is hemispherical. Find its curved surface area and volume.

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

Part $I$	Part $II$
$1.$ $CSA$ of a cylinder	$a.$ $3\pi r^2$
$2.$ $CSA$ of a sphere	$b.$ $2\pi rh$
$3.$ $CSA$ of a cone	$c.$ $4\pi r^2$
$4.$ $TSA$ of a hemisphere	$d.$ $\pi rl$

How many balls of radius $0.5\, cm$ can be produced by melting a metallic cylinder with radius $4\, cm$ and height $3\, cm$?

Water is flowing at the rate of $15\, km/h$ through a pipe of diameter $14\, cm$ into a cuboidal pond which is $50\, m$ long and $44\, m$ wide. In what time will the level of water in the pond rise by $21\, cm$? (in $h$)

$TSA$ of a cone with radius $4\, cm$ and height $3\, cm$ is $\ldots \ldots \ldots \ldots cm^{2}$. (in $\pi$)