a. 120 units of end item Z are needed at the beginning of week 7 . On hand balances: Z=40,A70,B=100, and C=30 units. There is a scheduled receipt of 20 units of C in week 4. Lead times are 2 weeks for Z and B, and 1 week for other items. Lot-for-lot ordering is used for all items. The product structure tree is shown below: Prepare a material requirements plan for component C : We will need to prepare material plans for Z, A, B, and C. Answer is complete but not entirely correct