$14\mathrm{.}3$ The demand for subassembly $\backslash ($ S $\backslash )$ is $100$ units in week $7.$

Each unit of $5$ requires $1$ unit of $\backslash ($ T $\backslash )$ and $2$ units of $\backslash ($ U $\backslash ).$ Each unit of T requires $1$ unit of V$,2$ units of W$,$ and $1$ unit of X$.$ Finally, each unit of $\backslash ($ U $\backslash )$ requires $2$ units of $\backslash ($ Y $\backslash )$ and $3$ units of Z $.$ One firm manufactures all items. It takes $2$ weeks to make $\backslash (\backslash$mathrm$\{$S$\},1\backslash )$ week to make T$,2$ weeks to make U$,2$ weeks to make V$,3$ weeks to make $\backslash (\backslash$mathrm$\{$W$\},1\backslash )$ week to make X$,2$ weeks to make X $,$ and $1$ week to make Z $.$

a$)$ Construct a product structure. Identify all levels, parents, and components.

b$)$ Prepare a time$-$phased product structure.