A maker of polypropylene (PP) garden furniture is concerned that the competition is stealing part of his market by claiming that the “traditional” material for garden furniture, cast iron, is much...

A maker of polypropylene (PP) garden furniture is concerned that the competition is stealing part of his market by claiming that the “traditional” material for garden furniture, cast iron, is much less energy- and CO₂-intensive than the PP. A typical PP chair weighs 1.6 kg; one made of cast iron weighs 11 kg. Use the data sheets for these two materials in Chapter 15 to find out who is right—are the differences significant? (Remember the warning about precision at the start of Chapter 6.)

If the PP chair lasts 5 years and the cast iron chair lasts 25 years, does the conclusion change?