$2$ A simple product has $8$ elements $($a to h$)$ whose times and immediate predecessors are shown in Table $7\mathrm{.}5.$ Devise a product layout that will produce products at a rate of at least $6$ products an hour. How many people will be required for this layout, and what will be its balancing loss?

Table $7\mathrm{.}5$ The immediate predecessors table for a simple product