A Firm Is Planning to Set Up an Assembly Line

A firm is planning to set up an assembly line to assemble 40 units per hour, and 57 minutes per hour are productive. The time to perform each task and the tasks which precede each task are:
$$\begin{array} { | c | c | c | } \hline \text { Task } & \begin{array} { c } \text { Preceding } \\\text { Task }\end{array} & \begin{array} { c } \text { Time to } \\\text { perform (min.) }\end{array} \\\hline \mathrm { A } & - - & .69 \\\hline \mathrm { B } & \mathrm { A } & .55 \\\hline \mathrm { C } & \mathrm { B } & .92 \\\hline \mathrm { D } & \mathrm { B } & .59 \\\hline \mathrm { E } & \mathrm { B } & .70 \\\hline \mathrm { F } & \mathrm { B } & 1.10 \\\hline \mathrm { G } & \mathrm { C } , \mathrm { D } , \mathrm { E } & .75 \\\hline \mathrm { H } & \mathrm { G } , \mathrm { F } & .43 \\\hline \mathrm { I } & \mathrm { H } & .29 \\\hline\end{array}$$ a. Draw a network diagram of precedence relationships.
b. Compute the required cycle time per unit in minutes.
c. Compute the theoretical minimum number of workstations required to produce 40 units per hour.
d. Balance this line using longest processing time.
e. What is the efficiency of the line obtained in part d?