(a(i))[4]
Show that the volume of lamp $A$ is $650\text{ cm}^3$, correct to $3$ significant figures.
(a(ii))[3]
Calculate the curved surface area for lamp $A$.
(a(iii))[2]
Lamp $B$ is mathematically similar to lamp $A$. The volume of lamp $B$ is $450\text{ cm}^3$. Calculate the total height of lamp $B$.
(b)[3]
The mass of lamp $C$ is $340\text{ g}$, correct to the nearest $10\text{ g}$. $8$ of these lamps are put into a packing case. The combined mass of the packing case and the $8$ lamps is $4.2\text{ kg}$, correct to the nearest $0.1\text{ kg}$. Calculate the upper bound of the mass of the packing case when empty. Give your answer in kilograms.