Samuel? Smith's company wants to establish an assembly line to manufacture its new? product, the iStar phone.? Samuel's goal is to produce 60 iStars per hour.? Tasks, task? times, and immediate predecessors are as? follows:

Activity	Performance Time (seconds)	Predecessors	Activity	Performance Time (seconds)	Predecessors
A	45	-	F	25	C
B	35	A	G	16	C
C	54	A	H	22	D, E
D	41	B	I	20	F, G
E	10	B	J	40	H, I

a) The theoretical minimum number of workstations that Samuel can achieve in the assembly line? =

c) The actual number of workstations used by Samuel in designing the assembly line in? (b) for the iStar phone? =

d) The operating efficiency of the assembly line in? (b) =