One unit of a is made of three units of b, one unit of c, and two units of d. b is composed of two units of e and one unit of d. c is made of one unit of b and two units of e. e is made of one unit of f. items b, c, e, and f have one-week lead times; a and d have lead times of two weeks. assume that lot-for-lot (l4l) lot sizing is used for items a, b, and f; lots of size 50, 50, and 175 are used for items c, d, and e, respectively. items c, e, and f have on-hand (beginning) inventories of 10, 50, and 160, respectively; all other items have zero beginning inventory. we are scheduled to receive 10 units of a in week 2, 50 units of e in week 1, and also 40 units of f in week 1. there are no other scheduled receipts. if 30 units of a are required in week 8, use the low-level-coded bill of materials to find the necessary planned order releases for all components. develop an mrp planning schedule showing gross and net requirements and order release and order receipt dates.