$[5]$

Material requirements planning $($MRP$)$ is used to plan and control material requirements. The master production schedule $($MPS$)$ for three sizes of screwdrivers is given in the table. All three screwdrivers $(4mm,6mm$ and Star $8)$ use the same handle. The MPS requirements are:

The inventory record $($item master file$)$ shows the following planning factors: batches are set at quantities of $20$ ; safety stock is set at $2$ handles; the available inventory is $70$ and the lead time for orders is two weeks.

$4\mathrm{.}1$ In which week will the first order be issued?

$4\mathrm{.}2$ In which week will the second order be issued?

$4\mathrm{.}3$ What will the available inventory be in week $3?$

$4\mathrm{.}4$ What will the available inventory be in week $5?$

$4\mathrm{.}5$ How many items are included in the safety stock to begin with?

$\backslash$table$[[,$Week $0,$Week $1,$Week $2,$Week $3,$Week $4,$Week $5],[\backslash$table$[[$Gross$],[$required$]],,,,,,],[\backslash$table$[[$Available$],[$inventory$]],,,,,,],[\backslash$table$[[$Planned$],[$order$]],,,,,,]]$