The radius and height of a right circular cone are in the ratio $5:12$. If its volume is $314 \frac{3}{7} \text{ m}^3$,find the radius of the cone (in $\text{m}$).

$A$ cylindrical vessel of radius $4 \, cm$ contains water. $A$ solid sphere of radius $3 \, cm$ is lowered into the water until it is completely immersed. The water level in the vessel will rise by (in $cm$)

$2$ cubes,each of side $12\, cm$,are joined end-to-end. The surface area of the resulting cuboid is...........$cm^2$.

Find out the amount of concrete required to erect a concrete pillar whose circular base has a perimeter of $8.8\, m$ and whose curved surface area is $17.6\, m^2$. $\left(\pi=\frac{22}{7}\right)$

$A$ hollow hemispherical bowl is made of silver with its outer radius $8\, cm$ and inner radius $4\, cm$. The bowl is melted to form a solid right circular cone of radius $8\, cm$. The height of the cone formed is......$cm$

$66 \text{ cm}^3$ of silver is drawn into a wire $1 \text{ mm}$ in diameter. The length of the wire in metres will be