The volume of a sphere is $4.5 \pi \, cm^3$. Then,its diameter is $\ldots \ldots \ldots \ldots cm$.

$A$ gulab jamun contains sugar syrup up to about $30\%$ of its volume. Find approximately how much syrup would be found in $45$ gulab jamuns,each shaped like a cylinder with two hemispherical ends with length $5\,cm$ and diameter $2.8\,cm$ (see figure) (in $cm^3$) [take $\pi=\frac{22}{7}$].

The base of a cone with radius $6 \, cm$ and height $8 \, cm$ is hemispherical. Find the curved surface area and the volume of the solid. $(\pi = 3.14)$

$A$ milk container of height $16 \, cm$ is made of metal sheet in the form of a frustum of a cone with radii of its lower and upper ends as $8 \, cm$ and $20 \, cm$ respectively. Find the cost of milk at the rate of $Rs. \, 22$ per $litre$ which the container can hold. (in $Rs.$)

$A$ solid toy is in the form of a hemisphere surmounted by a right circular cone. The height of the cone is $2 \, cm$ and the diameter of the base is $4 \, cm$. Determine the volume of the toy. If a right circular cylinder circumscribes the toy,find the difference of the volumes of the cylinder and the toy. (in $cm^3$) (Take $\pi = 3.14$)

The diameters of a frustum of a cone are $32 \,cm$ and $20 \,cm$. If its height is $8 \,cm$,find its curved surface area and volume. $(\pi = 3.14)$