1. Material F.3 D & T Shun Lee Catholic Secondary School

2. Choose an appropriate material Cost Availability Properties Durability Maintenance

3. Steel Steel is strong and quite cheap. The main problem is it rusts. We can paint the steel or use stainless steel to solve the problem.

4. Plastics It is easily moulded. It is water resistant. It does not rust. It has large range of properties. It is very strong for its weight. It is very cheap.

5. Wood It is heavy. It is quite cheap. It is quite strong.

6. Concrete It is water resistant. It can be moulded. It does not rust.

7. Concrete - moulding