In order:
A car rolls by using it's wheels.
Cars are made from many materials. Bodies can be made of metal, plastics, aluminum or even carbon fibers. Wheels and internal parts have many materials as well.
rubber
To make a car that has wheels made out of compact discs, everything else must be in porportion.
the wheel is made of rubber
Most commonly steel or aluminium, some have been made of carbon fibre and others of Plexiglas
Standard car and truck wheels are made of steel, "alloy" wheels are made of a lightweight aluminum alloy.
Casting Casting
Carbon...
In China
Aluminum
It has been tryed with three wheels but it is not convinient for safety.