LecturerToday we'll look at plastic — a material so useful, and so common, that it now turns up almost everywhere on Earth.
LecturerMost plastic is made from oil, which is heated and treated until it forms long chains we can mould into any shape.
LecturerIts great strengths are obvious: it is cheap, light, and above all it does not rust or rot easily.
LecturerBut that last strength is also its curse. Because it does not rot, a single bottle can last for hundreds of years.
LecturerRecycling helps. The first step at the plant is always to sort the plastic by type, since the kinds cannot be mixed.
LecturerThe sorted plastic is then washed, chopped into small flakes, and finally melted down to be used again.
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