Find the cost of sinking a tube well $280 \mathrm{m}$ deep, having diameter $3 \mathrm{m}$ at the rate of $₹3.60$ per cubic metre. Find also the cost of cementing its inner curved surface at $₹2.50$ per square metre.

$2.2$ cubic dm of brass is to be drawn into a cylindrical wire $0.25 \mathrm{cm}$ in diameter. Find the length of the wire. (Take $\mathrm{\pi }=\frac{22}{7}$)

A well with $10 \mathrm{m}$ inside diameter is dug $8.4 \mathrm{m}$ deep. Earth taken out of it is spread all around it to a width of $7.5 \mathrm{m}$ to form an embankment. Find the height of the embankment. (Take $\mathrm{\pi }=\frac{22}{7}$)

A hollow garden roller, $63 \mathrm{cm}$ wide with a girth of $440 \mathrm{cm}$, is made of $4 \mathrm{cm}$ thick iron. If the volume of the iron is $\mathrm{k} {\mathrm{cm}}^3$, then find $\mathrm{k}$ considering $\mathrm{\pi }=\frac{22}{7}$.

In the middle of a rectangular field measuring $30 \mathrm{m} \times 20 \mathrm{m}$ a well of $7 \mathrm{m}$ diameter and $10 \mathrm{m}$ depth is dug. The earth so removed is evenly spread over the remaining part of the field. Find the height through which the level of the field is raised.