Classify the following fibres into natural and man-made: cotton, nylon, jute, wool, silk, rayon, polyester?
[List: Soap, paint, urea, detergent, glass, cement, thermoplastic, calcium-ammonium nitrate, quinine, methane]
Statement: A man-made material used extensively in protecting articles made of wood and iron-___________
Some objects and some materials are listed below. Match the object with the material it is usually made of.