$A$ spherical glass vessel has a cylindrical neck $8 \, cm$ long and $2 \, cm$ in diameter. The diameter of the spherical part is $8.5 \, cm$. By measuring the amount of water it holds,a child finds its volume to be $345 \, cm^{3}$. Check whether she is correct,taking the above as the inside measurements,and $\pi = 3.14$. (in $, cm^{3}$)

$A$ juice seller was serving his customers using glasses as shown in the figure. The inner diameter of the cylindrical glass was $5 \, cm$,but the bottom of the glass had a hemispherical raised portion which reduced the capacity of the glass. If the height of a glass was $10 \, cm$,find the apparent capacity of the glass and its actual capacity (in $cm^3$). (Use $\pi = 3.14$)

The slant height of a frustum of a cone is $4 \,cm$ and the perimeters (circumference) of its circular ends are $18 \,cm$ and $6 \,cm$. Find the curved surface area of the frustum in $cm^2$.

Derive the formula for the volume of the frustum of a cone.

$A$ pen stand made of wood is in the shape of a cuboid with four conical depressions to hold pens. The dimensions of the cuboid are $15 \, cm$ by $10 \, cm$ by $3.5 \, cm$. The radius of each of the depressions is $0.5 \, cm$ and the depth is $1.4 \, cm$. Find the volume of wood in the entire stand (in $cm^3$). [Take $\pi = \frac{22}{7}$]

The radii of the ends of a frustum of a cone $45\, cm$ high are $28\, cm$ and $7\, cm$ (see figure). Find its volume,the curved surface area,and the total surface area (Take $\pi=\frac{22}{7}$).