The demand for subassembly $\backslash ($ S $\backslash )$ is $90$ units in week $7.$ Each unit of $\backslash ($ S $\backslash )$ requires $2$ units of $\backslash ($ T $\backslash )$ and $1$ unit of $\backslash ($ U $\backslash ).$ Each unit of $\backslash ($ T $\backslash )$ requires $2$ units of $\backslash ($ V$,2\backslash )$ units of $\backslash ($ W $\backslash ),$ and $2$ units of $\backslash ($ X $\backslash ).$ Finally, each unit of $\backslash ($ U $\backslash )$ requires $1$ unit of $\backslash ($ Y $\backslash )$ and $3$ units of $\backslash ($ Z $\backslash ).$ One firm manufactures all items. It takes $2$ weeks to make $\backslash (\backslash$mathrm$\{$S$\},2\backslash )$ weeks to make T$,2$ weeks to make $\backslash ($ U $\backslash ),1$ week to make $\backslash (\backslash$mathrm$\{$V$\},2\backslash )$ weeks to make $\backslash (\backslash$mathrm$\{$W$\},2\backslash )$ weeks to make X $,2$ weeks to make $\backslash ($ Y $\backslash ),$ and $2$ weeks to make $\backslash ($ Z $\backslash ).$

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In addition to $90$ units of $\backslash ($ S $\backslash ),$ there is also a demand for $20$ units of $\backslash ($ U $\backslash ),$ which is a component of $\backslash ($ S $\backslash ).$ The $20$ units of $\backslash ($ U $\backslash )$ are needed for maintenance purposes. These units are needed in week $6.$ Modify the gross material requirements plan to reflect this change $($type $0$ if the input box is not used$).$