Total surface area of a closed cube $= \dots$

The radius and height of a cylinder are $1.4 \, cm$ and $10 \, cm$ respectively. Then,its curved surface area is $\ldots \ldots \ldots \, cm^2$.

$A$ building is in the form of a cylinder surmounted by a hemispherical vaulted dome and contains $41 \frac{19}{21} \, m^3$ of air. If the internal diameter of the dome is equal to its total height above the floor,find the height of the building? (in $m$)

The volume of a cylinder with radius and height both $5 \, cm$ is $\ldots \ldots \ldots \pi \, cm^{3}$.

The radii of a bucket in the shape of a frustum of a cone are $28 \, cm$ and $21 \, cm$. If its capacity is $28.490 \, \text{litres}$, find its height in $cm$.

How many balls of radius $0.5\, cm$ can be produced by melting a metallic cylinder with radius $4\, cm$ and height $3\, cm$?