$A$ solid iron pole consists of a cylinder of height $220 \,cm$ and base diameter $24 \,cm$,which is surmounted by another cylinder of height $60 \,cm$ and radius $8 \,cm$. Find the mass of the pole,given that $1 \,cm^3$ of iron has approximately $8 \,g$ mass. (in $kg$) (Use $\pi = 3.14$)

$A$ farmer connects a pipe of internal diameter $20 \,cm$ from a canal into a cylindrical tank in her field,which is $10 \,m$ in diameter and $2 \,m$ deep. If water flows through the pipe at the rate of $3 \,km/h$,in how much time will the tank be filled? (in $minutes$) [Take $\pi = \frac{22}{7}$]

Derive the formula for the volume of the frustum of a cone.

Rachel,an engineering student,was asked to make a model shaped like a cylinder with two cones attached at its two ends by using a thin aluminium sheet. The diameter of the model is $3\, cm$ and its total length is $12\, cm$. If each cone has a height of $2\, cm$,find the volume of air contained in the model that Rachel made. (Assume the outer and inner dimensions of the model to be nearly the same.) Unless stated otherwise,take $\pi = \frac{22}{7}$. (in $cm^3$)

$A$ copper rod of diameter $1 \,cm$ and length $8 \,cm$ is drawn into a wire of length $18 \,m$ of uniform thickness. Find the thickness of the wire. (in $mm$)

$A$ $20\, m$ deep well with diameter $7\, m$ is dug and the earth from digging is evenly spread out to form a platform $22\, m$ by $14\, m$. Find the height of the platform. (in $m$) [Take $\pi=\frac{22}{7}$]