Problem $6-22($Algo$)$

Francis Johnson$$s plant needs to design an efficient assembly line to make a new product. The assembly line needs to produce $30$ units per hour, and there is room for only four workstations. The tasks and the order in which they must be performed are shown in the following table. Tasks cannot be split, and it would be too expensive to duplicate any task.

TASK TASK TIME $($MINUTES$)$ IMMEDIATE PREDECESSOR

A $1\mathrm{.}0$

B $0\mathrm{.}5$

C $1\mathrm{.}0$

D $1\mathrm{.}0$ A$,$ B$,$ C

E $1\mathrm{.}5$ C

F $1\mathrm{.}0$ E

G $1\mathrm{.}0$ E

What is the workstation cycle time required to produce $30$ units per hour?

Note: Round your answer to $1$ decimal place.

Balance the line to use the fewest possible workstations to meet the cycle time found in part $($b$).$ Use whatever method you feel is appropriate. What is the efficiency of your line balance, assuming the line operates at the cycle time from part $($b$)?$

Note: Round your answer to $1$ decimal place. Efficency $\%$