A product has a work distribution as shown by the precedence relationship diagram in Figure 10.26. The number above a node indicates the time in minutes needed to perform that particular operation. A closed-loop hook conveyor system is to be built that will produce 30 items/hour. Four other products are to be built on the same conveyor system with the dimensions (W x L) shown in the accompanying table. If the number of stations needed, the length of conveyor if the length is to be at least 1.5 times the minimum required length for storing the united and the spacing between stations is to be 2 feet. The input/output rates to the system can be 30 and 20 units/hour per person, respectively, and these stations are in addition to the stations necessary for the assembly jobs. The work on the input/output station can be speeded up by increasing the number of persons. For example two workers can unload 60 units/hour.