4.2 Dr Lori, the operations manager at Nesa Electronics, prides herself on excellent assembly-line balancing. She has been told that the firm needs to complete 120 instruments per 24-hour day. The assembly line activities, their precedence relationship and their activity times are shown in the table below:

Task	A	B	C	D	E	F	G	H	I	J
Immediate Predecessor	-	-	B	C	B	A,E	-	D, F, G	H	I
Task Time (minutes)	7	4	5	6	3	4	6	4	5	2

4.2.1 Draw the precedence diagram. (4)

4.2.2 Determine the highest allowable cycle time. (2)

4.2.3 If the cycle time after allowance is given as 10 minutes, what is the daily (24-hour) production rate? (2)

4.2.4 With a 10-minutes allowable cycle time, calculate the theoretical number of workstations. (2)

4.2.5 With a 10-minutes cycle time and six workstation, calculate the efficiency. (2)

4.2.6 Assign tasks to workstations without exceeding a 10-minute cycle time, and show the cumulative station time and the unassigned station time. (6)