If the radius of a sphere is doubled,its volume becomes $\ldots \ldots \ldots$ times the volume of the original sphere.

If the radius of a sphere is doubled,its volume becomes $\ldots \ldots \ldots \ldots$ times the original volume.

$A$ bucket is in the form of a frustum of a cone and holds $28.490 \, \text{litres}$ of water. The radii of the top and bottom are $28 \, \text{cm}$ and $21 \, \text{cm}$, respectively. Find the height of the bucket. (in $\text{cm}$)

$A$ solid consisting of a right circular cone of height $120\, cm$ and radius $60\, cm$ standing on a hemisphere of radius $60\, cm$ is placed upright in a right circular cylinder full of water such that it touches the bottom. Find the volume of water left in the cylinder,if the radius of the cylinder is $60\, cm$ and its height is $180\, cm$. [Take $\pi = \frac{22}{7}$.] (in $m^3$)

If the radius of a sphere is doubled,its volume becomes $\ldots \ldots \ldots \ldots$ times the original volume.

Shanta runs an industry in a shed which is in the shape of a cuboid surmounted by a half cylinder (see figure). If the base of the shed is of dimension $7\,m \times 15\,m,$ and the height of the cuboidal portion is $8\,m,$ find the volume of air that the shed can hold. Further,suppose the machinery in the shed occupies a total space of $300\,m^3,$ and there are $20$ workers,each of whom occupy about $0.08\,m^3$ space on an average. Then,how much air is in the shed? (in $m^3$) (Take $\pi = \frac{22}{7}$)