$A$ 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 $\pi = \frac{22}{7}$]

$A$ wooden article was made by scooping out a hemisphere from each end of a solid cylinder,as shown in the figure. If the height of the cylinder is $10 \, cm$ and its base radius is $3.5 \, cm$,find the total surface area of the article (in $cm^2$).

$A$ metallic sphere of radius $4.2 \, cm$ is melted and recast into the shape of a cylinder of radius $6 \, cm$. Find the height of the cylinder. (in $cm$) [Take $\pi = \frac{22}{7}$]

$A$ metallic right circular cone $20 \, cm$ high and whose vertical angle is $60^{\circ}$ is cut into two parts at the middle of its height by a plane parallel to its base. If the frustum so obtained is drawn into a wire of diameter $\frac{1}{16} \, cm$,find the length of the wire in meters. [Use $\pi = \frac{22}{7}$]

$A$ tent is in the shape of a cylinder surmounted by a conical top. If the height and diameter of the cylindrical part are $2.1 \, m$ and $4 \, m$ respectively,and the slant height of the top is $2.8 \, m$,find the area of the canvas used for making the tent. Also,find the cost of the canvas of the tent at the rate of $Rs. \, 500$ per $m^2$. (in $Rs.$) [Use $\pi = \frac{22}{7}$] (Note that the base of the tent will not be covered with canvas.)

$A$ $20\, m$ 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 $\pi=\frac{22}{7}$]