$4\mathrm{.}2$ The demand for cell phones in a cell phone production company in Doornfontein is $2600$ units per $12-$hour shift. The production line efficiency is $88\%$ and employee personal time is $2$ hours per shift. The individual workstation cycle times are given in Table Q$4$ below.

Table Q$4$: Workstation cycle times

Workstation Number Cycle Times $($minutes$)$

$0010\mathrm{.}744$

$0030\mathrm{.}521$

$0050\mathrm{.}705$

$0070\mathrm{.}438$

$0091\mathrm{.}000$

$0110\mathrm{.}382$

$4\mathrm{.}2\mathrm{.}1$ Identify the bottleneck station, balance the assembly line and calculation the line efficiency.

$4\mathrm{.}2\mathrm{.}2$ After your initial balancing in question $4\mathrm{.}2\mathrm{.}1$ above, identify the new bottleneck station, re$-$balance the assembly line, determine the level and line efficiency and interpret your answer.