As an engineer, you are tasked with designing a lighting system that consists of four $20$ W bulbs and one switch to control all four bulbs simultaneously. To achieve uniform brightness, it is crucial to connect the bulbs using suitable techniques. Provide the schematic circuit design and all relevant calculations necessary to meet the given specifications, considering a supply voltage of $80$ V $.$ Predict what will happen when one of the light bulbs burns out, leading to an open circuit. Justify your answer using appropriate calculations.

$(5$ Marks$)$

Resistivity, $$ of different materials are listed in Table $1.$

i$.$ Calculate the resistance of each material if the diameter of the wire is $0\mathrm{.}35$ mm and the length is $16$ m $.$

Table $1$

$\backslash$table$[[$Type of Material,Resistivity $(.m)$