The radius of the base of a conical tent is $5 \, m$. If the tent is $12 \, m$ high,then the area of the canvas required to make the tent is (in $\pi \, m^2$)

If a sphere of radius $r$ is divided into $4$ identical parts,then the total surface area of the $4$ parts is

Water flows into a tank with a base of $150\, m \times 100\, m$ through a pipe with a cross-section of $2\, dm \times 1.5\, dm$ at a speed of $15\, km/h$. In what time will the water reach a depth of $3\, m$? (in $hours$)

$2$ cans have the same height equal to $21\, cm$. One can is cylindrical,the diameter of whose base is $10\, cm$. The other can has a square base of side $10\, cm$. What is the difference between their capacities? (in $cm^3$)

$A$ solid metallic spherical ball of diameter $6\, cm$ is melted and recast into a cone with diameter of the base as $12\, cm$. The height of the cone is........$cm$

If the side of a cube is increased by $100 \%$,its volume is increased by (in $\%$)