Total surface area of a cylinder $= \dots$

$A$ metallic cone with radius $5 \, cm$ and height $8 \, cm$ is melted and recast to produce identical balls with diameter $0.5 \, cm$. Find the number of balls produced.

$A$ plumbline (sahul) is the combination of (see figure):

The volume of a hemisphere with diameter $1 \, cm$ is $\ldots \ldots \, cm^3$.

Total surface area of a closed cube with length $4 \, cm$ is $\ldots \ldots \ldots cm^{2}$.

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. $(\pi = 3.14)$