80 units of end item x are needed at the beginning of week 6, and another 30 units are needed at the beginning of week 8. Prepare a material requirements plan for component d. d can only be ordered in whole cases (60 units per case). on case of d is automatically received every other week, beginning in week 1. also, there are 80 units of b and 50 units of d now on hand. lead times for all items are a function of quality: one week for up to 100 units, two weeks for 101 to 200 units, three weeks for 201 to 300 units and four weeks for 301 or more units"