If a hemisphere is melted and four spheres of equal volume are made,the radius of each sphere will be equal to

$A$ field is in the form of a rectangle of length $18\, m$ and width $15\, m$. $A$ pit,$7.5\, m$ long,$6\, m$ broad and $0.8\, m$ deep,is dug in a corner of the field and the earth taken out is evenly spread over the remaining area of the field. The level of the field raised is......$cm$

The height of a right circular cone and the radius of its circular base are $9 \, cm$ and $3 \, cm$ respectively. The cone is cut by a plane parallel to its base so as to divide it into two parts. The volume of the frustum (i.e.,the lower part) of the cone is $44 \, cm^3$. The radius of the upper circular surface of the frustum $\left(\text{taking } \pi = \frac{22}{7}\right)$ is

$A$ solid cylinder has a base radius of $14\, cm$ and a height of $15\, cm$. Identical small cylinders are cut from each base as shown in the figure. The height of each small cylinder is $5\, cm$ and the radius is $7\, cm$. What is the total surface area (in $cm^2$) of the remaining part?

$A$ metallic sheet is of rectangular shape with dimensions $48\, m \times 36\, m$. From each of its corners, a square is cut off so as to make an open box. If the length of the side of the square is $8\, m$, the volume of the box (in $m^3$) is:

Find the length of the canvas $2 \ m$ in width required to make a conical tent $12 \ m$ in diameter and $6.3 \ m$ in slant height (in $m$).