Eighty units of product E are needed at the beginning of week 6. Three cases (30 units per case) of J have been ordered and one case is scheduled to arrive in week 3, one in week 4, and one in week 5. Note: J must be ordered by the case, and B must be produced in multiples of 120 units. There are 60 units of B and 20 units of J on hand now. Manufacturing lead times are two weeks each for E and B, and purchase lead time is one week for J.

a. Prepare the materiel requirements plan for component J.
b. Suppose that now is week 4 and the quantity of E needed in week 6 has changed from 80 to 70. The planned order releases through week 3 and scheduled receipts have all been executed as in part α. How many more (relative to part a) Bs and Js will be on Land in week 6?