Lot Sizing Rule

SHOW WORK
3) FireKing Office Products, a manufacturer of fireproof file cabinets, uses MRP to schedule its production. Demand and inventory data for its “Signature Series Files” model are given in the table below. 
Period 1 2 3 4 5
Demand 20 40 30 10 45
Ordering Cost = $100 per order
Holding Cost = $1 per file cabinet per week
Lead Time = 1 period
Beginning Inventory = 25
Complete an MRP matrix for the “Signature Series Files” model using:
a) No lot sizing
b) Minimum 75 lot sizing
c) Multiple 50 lot sizing 
Which lot sizing rule do you recommend?