1. Product - bicycle The most important characteristic of a bicycle
Stability - strength, stiffness
Mobility - weight
Reasonable cost

2. Heat conductivity strength
Material & properties
Frame
< Strength Stiffness Light >
Steel
Carbon
Titanium
Heavy
Very light
Light
Chip
Expensive
Very expensive
Saddle
Outside
Inside
Leather
Sponge
Waterproof
Soft
Wheel
Material
Aluminium
Properties
Heat conductivity strength

3. <Properties of cast iron> ductile, strong
Material & properties
Tire - rubber
Gear – cast iron
Reflector – glass + aluminium
< Properties of rubber>
high friction
absorb shock
<Properties of cast iron> ductile, strong
<Properties of glass>
reflect light