$10$ identical solid spherical balls of radius $3 \text{ cm}$ are melted to form a single sphere. In this process,$20 \%$ of the solid is wasted. What is the radius (in $\text{cm}$) of the resulting sphere?

$A$ $1 \, m^3$ of metal weighing $90 \, Kg$ is rolled into a square bar $9 \, m$ long. An exact cube is cut off from the bar. How much does it weigh? (in $kg$)

The length of a room is $12\, m$,width $8\, m$,and height $6\, m$. How many boxes will it hold if each box occupies $1.5\, m^3$ of space?

The volume of a solid cylinder whose base diameter is $14\, mm$ and length is $25\, mm$ is $3850\, mm^3$. If the length of the cylinder is doubled but the diameter is halved,what will be the volume of the resulting cylinder? (in $mm^3$)

The curved surface area of a circular cylinder of height $h$ and the slant surface area of a cone of slant height $2h$,having the same circular base,are in the ratio of:

The outer dimensions of a closed wooden box of $1 \text{ cm}$ thickness are $12 \text{ cm} \times 10 \text{ cm} \times 8 \text{ cm}$. Find the cost of the wood required to make the box if $1 \text{ cm}^3$ of wood costs $₹ 3.00$.