The demand for subassembly $S$ is $140$ units in week $7.$ Each unit of $S$ requires $2$ units of $T$ and $1$ unit of $U.$ Each unit of $T$

requires $1$ unit of $V,2$ units of $W,$ and $2$ units of $x.$ Finally, each unit of $U$ requires $2$ units of $Y$ and $3$ units of $Z.$ One firm

manufactures all items. It takes $2$ weeks to make $S,1$ week to make T$,2$ weeks to make $U,2$ weeks to make $V,3$ weeks

to make $W,1$ week to make $x,2$ weeks to make $Y,$ and $2$ weeks to make $Z.$

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In addition to $140$ units of $S,$ there is also a demand for $20$ units of $U,$ which is a component of $S.$ The $20$ units of $U$ 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$).$