$A$ semi-circular sheet of metal of diameter $28 \, cm$ is bent to form an open conical cup. Find the capacity of the cup. (in $, cm^3$)

The volume of a sphere is $4500 \pi \text{ cm}^3$,then its diameter is $\dots \text{ cm}$.

The radius of a cone is $10\, cm$ and the total surface area of a cone is $880\, cm^2$. Find the slant height in $cm$. (Use $\pi = 22/7$)

The curved surface area of a cylinder is $8800 \, cm^2$. If the radius of the cylinder is $28 \, cm$,find its volume in $cm^3$.

$A$ heap of wheat is in the form of a cone whose diameter is $42 \, m$ and height is $20 \, m$. The heap is to be covered by canvas to protect it from rain. If the price of canvas is $₹ 75$ per $m^2$,find the cost of the canvas required.

$1 \, m^{2} = \ldots \ldots \, cm^{2}$