The North Star computer company builds a computer designated model ST2015. The bill of materials of model ST2015 is described as follows:

• One end item (ST2015) requires 1 motherboard and 2 disk drives.

• A motherboard requires 3 add-in boards and 90 DRAM chips.

The company purchases disk drives and DRAM chips from outside suppliers. The lead times for purchasing disk drives and DRAM chips are 1 week and 2 weeks respectively. The company produces the add-in boards and assembles the motherboards in its own plant in Dallas, Texas. The manufacturing lead time for add-in boards is 1 week, and the assembling lead time for motherboards is 3 weeks. Furthermore, it takes 1 week for the company to assemble the computer.

Suppose that the forecasted demands for the computer for weeks 6 to 11 are 220, 165, 180, 120, 75, and 200. At the end of week 5, the inventory of assembled computers will be 75, and the production manager anticipates scheduled receipts of 30 in week 8 and 10 in week 10.

a) Develop an MRP table for the end item assuming a lot-for-lot scheduling rule.

b) Determine the planned-order-release for the motherboards assuming a lot-for-lot rule. Assume that there are no schedule receipts and projected on-hand for the motherboards.

Suppose that North Star has 23,000 DRAM chips in inventory. It has scheduled receipts of 3,000 chips in week 3. At the current time, the company purchases DRAM chips from an outside supplier who only allows North Star to order 20,000 chips each time. Furthermore, North Star estimates a 4% failure rate for the chips purchased from the supplier; that is, 4% of the 20,000 chips ordered are not usable.

c) Develop the MRP table for the DRAM chips.