Suppose demand for a power steering gear assembly is given by

Currently there are $150$ parts on hand. Production is planned by using the fixed order period method with one order encompassing demand from $2$ periods. The lead time is $2$ periods. Determine the planned order release schedule. What are the 'net requirements' in period $3?$

Question $3$

Using the data from above, what are the 'planned order releases' in period $7?$ Note this question asks about order releases, not order receipts.