1. You are asked to advise a client on which parcel delivery service to use to deliver parcels of differing sizes.  Linear Deliveries Inc. charges a flat rate of £2.25 per parcel, plus 40p times the mass of the parcel in kilograms.  Square Deal Delivery Solutions charges a flat rate of £4 per parcel, plus 1p times the square of the parcel’s mass in kilograms.  Under what circumstances would you advise your client to use each of the two delivery services?  Be sure to show clear mathematical justifications for your answer.