Assembling a pair of scissors requires a straight blade assembly, a bent blade assembly, and a screw. Each straight blade assembly requires a straight blade and a straight blade grip. Each bent blade assembly requires a bent blade and a bent blade grip. There is demand for 800 pair of scissors on day 8. There are on hand inventories of 100 straight blade assemblies, 50 bent blade assemblies, 300 front blades, 200 bent blades, 100 straight blade grips, 50 bent blade grips, and 500 screws. Lead time for assembling scissors is 1 day, and delivery lead times for straight blades and straight blade grips are 2 days, 3 days for bent blades and bent blade grips, and 1 day for screws.

Given this information:

1. Construct a product structure tree for a pair of scissors.

2. Assuming a lot-sizing rule of lot-for-lot, prepare a material requirements plan.